Kei Nishikori

Nishikori started his 2019 season at the Brisbane International, where he was seeded second. He defeated Denis Kudla, sixth seed Grigor Dimitrov, and Jérémy Chardy to reach the final, where he defeated fourth seed Daniil Medvedev in three sets to win the title. This was his first tournament victory since February 2016 and broke his streak of nine consecutive final losses.

As of 2019, after the dismissal of the Burn line, Nishikori currently endorses the Wilson Ultra 95.

Nishikori returned after a 5-month injury layoff and started his 2018 season by playing at the American challenger tour events. In Newport Beach he lost in the first round against American qualifier Dennis Novikov. In the following week, Novikov and Nishikori met again in the first round. This time, Nishikori won in straight sets. Kei Nishikori went on to win his next four matches en route to win his sixth ATP Challenger career titles in Dallas, by defeating Mackenzie McDonald in the final.

Wawrinka won their most recent meeting at the 2018 Cincinnati Masters.

At the 2018 US Open, Nishikori and Cilic again met in the quarterfinals. In a five set thriller, Nishikori won a spot in the semifinal of the US Open for only the third time (and only the third time advancing past the quarters in any of the four majors).

Nishikori made his return to the ATP Tour competition (since August 2017 Montreal) at the inaugural ATP 250 Tournament in New York. Nishikori made a back-to-back winning return in New York by defeating Noah Rubin and Evgeny Donskoy in the first and second round respectively. He defeated Radu Albot in the quarterfinals in three sets, before losing to Kevin Anderson in the semifinal. Kei Nishikori was unseeded at the 2018 Abierto Mexicano Telcel in Acapulco and lost against Denis Shapovalov in the first round.

He wears Uniqlo clothing and as of the beginning of 2017 red Nike Vapor Tour shoes after having played for almost a decade in Adidas. He is also sponsored by Nissin Foods, TAG Heuer, Fast Retailing, LVMH Moët Hennessy, Japanese financial services firm Jaccs Co., WOWOW, mattress topper Air Weave, EA Games, Delta Air Lines and Japan Airlines, in a deal which has his image emblazoned on a Boeing 777-300ER dubbed "JET-KEI". He is often seen wearing a Cup Noodles badge on his sleeve during matches. In 2011, he filmed a commercial for Morinaga & Company's sports drink Weider in Jelly. He also carries around a character called Mr. Saturn from the popular video game Mother / Earthbound.

Nishikori made his third successive appearance at the year-end championships after becoming the fifth player to qualify for the 2016 ATP World Tour Finals. He won his first match, upsetting third seed, Stan Wawrinka in straight sets 6–2, 6–3 before losing his other two round-robin matches to Andy Murray and Marin Čilić respectively, both in three sets. Having done enough to nevertheless make the semifinals however, he was then defeated by a resurgent Novak Djokovic in straight sets, ending his season with a singles ranking of world No. 5 for both the second time in his career and in the past three years as well.

Fresh from his Rogers Cup finals appearance in Toronto, Nishikori represented Japan at the Rio 2016 Olympics, where he was seeded 4th. In the semifinal he lost to Andy Murray and faced Rafael Nadal for the bronze medal match, which he won in 3 sets; it was the first Olympic tennis medal for Japan in 96 years.

They met 3 times in 2016. Nishikori won 2 of their 3 meetings in 2016. They both qualified for the 2016 ATP World Tour Finals and were drawn in the same group. Nishikori defeated Wawrinka in the round robin match.

Nishikori began the 2015 season by participating in the 2015 Brisbane International and reached the semifinals before being beaten by Milos Raonic in 3 tight-set tiebreaks. He reached the 2015 Brisbane International doubles finals with his partner Alexandr Dolgopolov but lost in straight sets. Nishikori equalled his best record yet in the Australian Open by reaching the quarterfinals for the second time in his career, dropping only 2 sets along the way, but he was beaten in straight sets by defending champion Stan Wawrinka. In February, Nishikori won his eighth singles title and became the first ever player to win the Memphis Open three times in a row, beating Kevin Anderson in straight sets in the final.

He next participated in the 2015 Abierto Mexicano Telcel and reached the final, losing only a set to Kevin Anderson in the semifinals. By reaching the final, he earned enough ATP ranking points to move into a new career high world ranking of No. 4. However, he lost to David Ferrer in straight sets in the final. During the March Masters, he reached the fourth round of the 2015 BNP Paribas Open for the first time in seven appearances but was upset by Feliciano López in straight sets in the fourth round. In the 2015 Miami Open, he defeated Mikhail Youzhny, Viktor Troicki and David Goffin all in straight sets losing only a total of 10 games to reach the quarterfinals. However, he was upset by an in-form John Isner in straight sets.

Nishikori began his clay-court season at the 2015 Barcelona Open Banc Sabadell where he reached the final after beating Teymuraz Gabashvili, Santiago Giraldo, Roberto Bautista Agut and Martin Kližan. He successfully defended his title by beating Pablo Andújar in the final in two sets to win his ninth career title on the tour. At the 2015 Mutua Madrid Open, Nishikori was granted a first-round bye and proceeded by defeating David Goffin in three tough-sets in the second round. He reached the semifinals after beating Roberto Bautista Agut and David Ferrer in straight sets respectively. He then lost to Andy Murray in the semifinals, and his ranking dropped to 6th as a result of failing to defend his points from the final in 2014.

Nishikori was given a tough draw at the 2015 Italian Open but managed to reach the quarterfinal after beating Jiří Veselý and Viktor Troicki, both in straight sets. He faced world No. 1 Novak Djokovic in the QF and lost in three sets. Nishikori opened his French Open campaign by defeating both Paul-Henri Mathieu and Thomaz Bellucci in straight sets to advance to the third round. He advanced to the 4R for the second time in his career after his third round opponent, Benjamin Becker, withdrew due to a right shoulder injury. Nishikori became the first Japanese man to reach the quarterfinals of the French Open in 82 years by beating Teymuraz Gabashvili. He then played home favorite Jo-Wilfried Tsonga, but eventually lost in five set.

Nishikori opened his hard-court season by competing at the 2015 Citi Open defeating James Duckworth, Leonardo Mayer, Sam Groth, and Marin Čilić en route to the final where he beat John Isner in three tight sets to capture his third title of the year and 10th title overall. At the 2015 Rogers Cup, he reached the semifinals without losing a set and defeated Rafael Nadal for the first time in eight tries in the quarterfinals. He lost to Andy Murray in the semifinals in straight sets. He withdrew from the Cincinnati Masters citing fatigue and hip injury, which affected his semifinal match against Murray the previous week. He lost in the first round of the 2015 US Open to Benoît Paire.

They met in another Grandslam quarterfinal, this time at the 2015 Australian Open. Wawrinka beat Nishikori in 3-straight-sets.

In 2015, the duo first met at the Brisbane International with Raonic prevailing in 3 tight-set tiebreaks. This was followed later on in the same year in the Davis Cup where Nishikori won in another epic five-setter to keep Japan's hopes for a quarterfinal place alive with the score tied again at 2–2.

In 2015, Ferrer had a remarkable start to the season but was beaten in the Australian Open by Nishikori in a dominant straight sets victory. However, Ferrer ended his losing streak to Nishikori in the Abierto Mexicano Telcel where he beat Nishikori in straight sets in the final. In Madrid, in the quarterfinals, Nishikori took revenge and beat him in straight sets.

In 2015, the pair met in the semifinals of the 2015 Citi Open, with Nishikori coming back from a set down to prevail in three, and gain a place in his 15th career final. They meet again later on in the 2015 Japan Open where Nishikori came back from a set down to defeat Cilic in three tight sets. In 2016, the duo met in the 4th round of the 2016 Wimbledon where Nishikori retired mid-match in the 2nd set after losing the first set due to a rib injury which had disrupted his grass season. They met again in the final of the Swiss Indoors, where Cilic prevailed in straight sets. During the round-robin stage of the Year-End 2016 ATP World Tour Finals, Cilic came from a set down to defeat Nishikori and ultimately prevail. Most recently, Nishikori defeated Cilic in the quarterfinals of the Monte-Carlo Masters by a score of 6–4, 6–7, 6–3.

From the 2015 to the 2018 season, Nishikori used the Wilson Burn 95.

Nishikori has won 12 singles titles and was runner-up at the 2014 US Open, making him the first male player representing an Asian country to reach a Grand Slam singles final. He also became the first man from Asia to qualify for the ATP World Tour Finals and reached the semifinals in 2014 and 2016. In addition, Nishikori defeated Rafael Nadal to win the bronze medal at the 2016 Summer Olympics, bringing Japan its first Olympic tennis medal in 96 years.

Michael Chang became Kei Nishikori's coach in 2014.

Nishikori bounced back from the French Open first round loss in the grass court season by reaching the semifinals of the 2014 Gerry Weber Open before losing to Roger Federer in straight sets. Nishikori participated in the Wimbledon Championships and made it to the fourth round after surviving a tight 5-setter against clay-court specialist Simone Bolelli, but eventually lost in the fourth round to Milos Raonic, despite winning the opening set. Nishikori opened his hard-court season by participating in the Citi Open. He reached the quarterfinals only to be beaten by Richard Gasquet for the fifth time in his career in straight sets.

Nishikori reached his first Grand Slam final at the 2014 US Open. He beat Wayne Odesnik, Pablo Andújar, Leonardo Mayer and then world No. 6 Milos Raonic in a marathon five-set match that lasted until 2:26 am, tying the record for late finishes at the US Open en route to the quarterfinals. In the quarterfinals, he scored a rare upset over Australian Open champion Stan Wawrinka, who had thus far dominated their meetings to ensure that he would regain a top ten ranking. He also became the first Japanese man in 81 years to reach the semifinals at a Major since Jiro Sato in 1933 French Championships (now French Open). Nishikori then defeated world No. 1 Novak Djokovic in the semifinals to become the first Asian man ever to reach a Grand Slam tournament final. (As reference, an American male tennis player of Asian descent Michael Chang reached the final of Grand Slam to win French Open at the youngest age of Grand Slam history, and the finalist to be Runner up in both US Open and Australian Open.) In the final, Nishikori lost to Marin Čilić. Nishikori's run at the US Open saw his singles ranking improve to world No.8.

Nishikori nearly replicated his 2014 US Open run by reaching the semifinals of the US Open, defeating Benjamin Becker, Karen Khachanov and Nicolas Mahut respectively in four sets, followed by a straight sets fourth-round win against Ivo Karlović, and a massive 5 set victory over world No. 2 Andy Murray in the quarterfinals that lasted nearly 4 hours; this was arguably his biggest victory since the 2014 US Open. After leading by a set and a break against eventual champion Stan Wawrinka in the semifinals, a clearly fatigued Nishikori lost in 4 sets, hence ending his U.S hardcourt season with a finals and semifinals run in the Canadian Open and the US Open respectively.

At the US Open, Nishikori was seeded 21st. He defeated Maximilian Marterer in straight sets in the first round, facing Gaël Monfils in the second. Monfils was forced to retire in the second set after sustaining a wrist injury during the match. Nishikori then defeated 13th seed Diego Schwartzman and Philipp Kohlschreiber to reach his third quarterfinal at the US Open. There, he faced Marin Čilić in a rematch of the 2014 final. He dropped the first set 2–6, but pulled out a close five-set victory, breaking Čilić in the final game of the fifth set to win 6–4. He advanced to the semifinals, losing to Novak Djokovic in straight sets, 6–3, 6–4, 6–2.

At the ATP Finals, Nishikori was seeded seventh. He was drawn in Group Lleyton Hewitt and faced second seed Roger Federer in his first match, defeating him in straight sets. This was Nishikori's first victory over Federer since 2014 and ended a six-match losing streak against him. He was eliminated in the group stage after losing his next two matches against Kevin Anderson and Dominic Thiem. He ended the season ranked World No. 9.

In the 2014 Davis Cup World Group first round in Tokyo, Japan defeated Canada 4–1, and Nishikori had a hand in three Japan victories in the tie. He beat Peter Polansky and Frank Dancevic in the singles rubbers, and teamed up with Yasutaka Uchiyama for a victory in doubles over Dancevic and Daniel Nestor. Japan advanced to the quarterfinals in the World Group for the first time, but Nishikori missed the quarterfinal against Czech Republic due to a left groin injury.

In 2014, their rivalry was more intense with 3 ATP meetings. They first met in 2014 at the Brisbane International where Nishikori beat him in three sets to book his semifinal spot. They met again at the clay courts of the Barcelona Open where Nishikori dominated Cilic in another straight sets victory where he would later go on to win his first title on clay. Their most significant meeting would be at the 2014 US Open, they met in the finals after Nishikori overpowered world No. 1 Novak Djokovic and Cilic overcame world No. 2 Roger Federer in the semifinals. Their meeting in the final made the 2014 US Open the first Grand Slam where none of Federer, Nadal and Djokovic reached the final since the 2005 Australian Open. However, Nishikori was defeated in straight sets by an in-form Marin Cilic in the final.

As a junior, he compiled a 73–37 win/loss record in singles and 53–31 in doubles, achieving a combined ranking of No. 7 in the world in July 2006.

In the Swiss Indoors Basel tournament Nishikori defeated an ailing world No. 1 Novak Djokovic to reach the final, coming back from a 4–5, 0–30 deficit in the second set. The win was only Djokovic's fourth loss of the season, second loss in a completed match, and first loss of a completed match on a non-clay surface. Nishikori was defeated in the final by Roger Federer. On the heels of the victory, Nishikori was granted special exemption into the 2011 BNP Paribas Masters and achieved a ranking of world No. 24.

In 2013 US Open first round, Nishikori lost to a lower-ranked opponent, this time to world No. 179 Dan Evans in straight sets.

Nishikori opened his grass-court season by participating in the Halle Open where he reached the semifinals, only to retire in his match against Andreas Seppi down 1–4 in the first set due to his calf injury which he attained in his quarterfinal match. Nishikori decided to play Wimbledon, and he reached the second round by beating Simone Bolelli in five sets for the second straight year but then withdrew from his second round match against Santiago Giraldo, due to his calf injury acting on him again during his first round match.

For the 5th consecutive year, Nishikori did not play in Monte Carlo and instead turned his focus to defending his Barcelona Open Banc Sabadell title. He reached the final without losing a set, but lost in straight sets to resurgent nine-time champion Rafael Nadal in the final. He followed his good run by reaching the semifinals in the Mutua Madrid Open, beating Fabio Fognini, Richard Gasquet for the first time in 7 meetings and rising teenage star Nick Kyrgios. He lost in the semifinal to Novak Djokovic in straight sets despite a close 2nd set. Nishikori then replicated his Madrid run by reaching the semifinals of the Italian Open for the first time after beating Viktor Troicki in the opener in three sets, followed by wins over Richard Gasquet and Dominic Thiem in straight sets. He lost in the semifinal against world Novak Djokovic in a marathon 3 hours three-setter despite winning the first set 6–2 and managed to pull off a tiebreak in the third set. He later participated at the French Open but unfortunately lost to an in-form Gasquet in the fourth round in 4 sets. Nishikori began his grass season at the Halle Open, but retired in the 2nd round due to a hip injury. His next tournament was at Wimbledon, where he retired in the fourth round against Marin Čilić, once again due to injury.

With Murray, Federer and Nadal absent, Nishikori was seeded 3rd for the Rogers Cup Masters in Toronto. After beating Grigor Dimitrov and Stan Wawrinka in the quarterfinals and semifinals respectively, Nishikori then lost to Djokovic in straight sets in the finals, going 0–5 so far in the season against the Serb. Nishikori then participated in the 2016 Summer Olympics, where he reached the semis before being defeated by World No. 2 Andy Murray in straight sets. However, he later acquired the bronze medal after he defeated Rafael Nadal 6–2, 6–7 (1), 6–3, becoming the first Japanese man to win an Olympic tennis medal since Ichiya Kumagae in the 1920 Summer Olympics.

Nishikori next represented Japan in the Davis Cup Play-Off against Ukraine and played in the doubles rubber alongside Yūichi Sugita, winning the match in straight sets, giving Japan an unassailable 3–0 lead to promote his country back into the 2017 Davis Cup World Group.

Nishikori and Wawrinka have met 9 times, with Nishikori trailing 4–5. Wawrinka won both of their first two meetings in 2012, in the 3rd Round of Cincinnati Masters and in the quarterfinal of Buenos Aires respectively. Nishikori recorded his first win against Wawrinka at the quarterfinal of the 2014 US Open in a thrilling tight five-sets match which saw Nishikori later became the eventual finalist of the tournament.

Nishikori and Raonic have met 7 times, with Nishikori leading their head-to-head 5–2. They met once in 2012, 4 times in 2014 and twice during the 2015 season. At their first meeting in the 2012 Rakuten Japan Open final, Nishikori won it in 3 sets. Their first meeting in 2014 was at the Madrid Masters with Nishikori winning in two tiebreak sets. In Wimbledon 2014 4R, Raonic scored his first win against Nishikori beating him in four sets to advance to the quarterfinals. They met again in the US Open 4R where the match tied the all-time latest finish for a match at the US Open with Nishikori prevailing in five tight-sets which lasted 4 hours and 19 minutes. They had a rematch of their 2012 final in the Rakuten Japan Open 2014 final where Nishikori won again in 3 sets.

Nishikori and Ferrer have met 14 times, with Nishikori leading 10–4. They met for the first time in the 2008 US Open with Nishikori registering his first win over a top-10 player, beating David Ferrer in a five-set thriller as a teenager. They next met again from 2011–2013 with Ferrer winning 3 times in straight sets and Nishikori winning only once in the Olympics at 2012 in three sets. However, in 2014, Nishikori showed that his 2–3 deficit head-to-head encounter against Ferrer was just the beginning and thrashed the Spaniard in each of the 4 encounters in 2014. They first met in 2014 in the Miami Masters with Nishikori beating Ferrer in 3 tight-sets after saving 4 match points to progress to the QF. They next had an epic encounter at the Madrid Open with Nishikori beating Ferrer in another tight 3-setter to progress to the final of a Masters 1000 for the first time in his career. Their next 2 encounters were in the BNP Paribas Masters and the ATP World Tour Finals where Nishikori again defeated the Spaniard in 3 sets.

Nishikori and Cilic have met 16 times, with Nishikori leading 10–6. Cilic won their first ATP World Tour meeting in 2008 at Indian Wells, beating Nishikori in straight sets in the first round. In 2010, Nishikori avenged that loss at the US Open, beating Cilic in a tough five-setter lasting almost five hours. In 2011, they met at the Chennai Open where Nishikori beat Cilic in three sets. In 2012, they encountered each other at the US Open where Cilic avenged his past US Open loss to Nishikori by beating him in four sets to progress to the 4R. In 2013, they met at the Memphis Open where Nishikori beat him in straight sets to progress to the SF and he would later go on to win the title.

Nishikori started the season at the Brisbane International, where he lost in the second round to Marcos Baghdatis. At the 2012 Australian Open, Nishikori came back from a set down to defeat sixth seed Jo-Wilfried Tsonga to reach the quarterfinals of the Australian Open, where he was then defeated by fourth seed Andy Murray. Nishikori was the first Japanese male player to reach the quarterfinals of the Australian Open in 80 years.

Unfortunately, Nishikori withdrew from the US Open in Cincinnati with a right wrist problem and subsequent scans revealed a tear in one of the tendons. Soon after that, he announced that he would miss the rest of the season. As a result of his extended absence, following the conclusion of Paris he fell to World No.22, his lowest ranking since January 2012 and his first time out of the top 20 in the rankings since March 2014.

In a bid to regain match fitness, Nishikori entered the Monte-Carlo Masters for the first time since 2012, having never progressed past the third round at the tournament before. Unseeded for the tournament, he beat Tomas Berdych, Daniil Medvedev, Andreas Seppi, Marin Cilic, and Alexander Zverev to reach his 4th career Masters 1000 finals, before losing to Rafael Nadal in straight sets in the finals. Unfortunately, he thus became the active player with the most Masters 1000 finals without a title. At the 2018 Italian Open, he advanced past Feliciano López, third seed Grigor Dimitrov, and Philipp Kohlschreiber before losing to Novak Djokovic in the quarterfinals in three sets. At the 2018 French Open, Nishikori was seeded 19th. He defeated Maxime Janvier, Benoît Paire, and Gilles Simon before falling to seventh seed Dominic Thiem in the fourth round.

At the London 2012 Olympics, Nishikori competed in the singles and doubles competitions, partnering Go Soeda. In the singles, being 15th seed, he reached the quarterfinals, knocking out Bernard Tomic, Nikolay Davydenko, and fourth seed David Ferrer on the way. He became the first Japanese man to reach the quarterfinals since Takeichi Harada in the 1924 Paris Olympics. However, his run ended by eighth seed Juan Martín del Potro of Argentina. In the doubles, Nishikori and Soeda were eliminated in the first round by Switzerland's defending champions Roger Federer and Stan Wawrinka.

Nishikori has endorsed the Wilson Wilson Burn 95; however, it is believed by racquet enthusiasts that he used an older modified Wilson nCode nTour underneath the Steam paint job. In the past, special versions of the Steam racquet have been sold by Wilson, exclusively in Japan, capitalizing on Nishikori's popularity in his home country. Most recently, in 2012 the Steam Pro was available for sale, and was advertised as having the same specifications as Nishikori's actual racquet.

In the 2011 Australian Open, Nishikori reached the third round, defeating Fabio Fognini and Florian Mayer along the way. His run was ended in the third round by ninth seed Fernando Verdasco. After the third-round appearance in Melbourne, his ranking rose to No. 70.

At the first two ATP Masters Series events of the year, Nishikori suffered a first-round loss at Indian Wells and a second-round loss in Miami. Nishikori then reached his second final at the 2011 U.S. Men's Clay Court Championships. He was defeated by American wildcard Ryan Sweeting.

Nishikori began the season ranked No. 8. In January, he entered the Brisbane International as the No. 2 seed where he advanced to the quarterfinals with a bye and a straight sets win over Mikhail Kukushkin, but was eventually upset by seventh seed Bernard Tomic in three sets. At the Australian Open, Nishikori was seeded seventh. He began with victories over Philipp Kohlschreiber, Austin Krajicek and Guillermo García-López before beating ninth-seeded Jo-Wilfried Tsonga to reach his third Australian Open quarterfinal, where he lost to Novak Djokovic. Nishikori next competed at the Memphis Open where he was seeded first and was the three-time defending champion. Nishikori received a bye into the second round and advanced to the semifinals without dropping a set. In the semifinals, Nishikori beat Sam Querrey in three sets and later beat young American Taylor Fritz in straight sets to win his fourth straight Memphis title and his 11th ATP title overall. He joined Jimmy Connors as the only four-time winners of the event.

Kei made his comeback after his injury of the previous year. After receiving a wildcard at Delray Beach, he was beaten in the first round by Benjamin Becker. Kei returned to the Challenger tour later in April with great success, reaching quarterfinals at both Baton Rouge and Tallahassee events, followed by a victory at the Savannah Challenger over Ryan Sweeting in the final. On 15 May 2010, he won the Sarasota open by defeating Brian Dabul, in three sets.

Nishikori played in his first French Open. He rebounded from two sets down to defeat Santiago Giraldo of Colombia in the first round but he lost his second match against Novak Djokovic. He lost to Richard Gasquet in the first round of the 2010 Aegon Championships. At Wimbledon, he played second seed Rafael Nadal in the first round and lost in straight sets.

At the U.S. Open, the Japanese No. 1 met Marin Čilić in the second round. Nishikori ousted the 11th seed in 5 sets to advance to the third round, his best Grand Slam tournament showing in 2010.

Nishikori lost in the first round of the Miami Masters to the Spanish player Albert Montañés. He faced James Blake again, this time at the River Oaks International tournament in Houston, Texas in the first round, but Kei lost in two sets. He went out in the third round of the 2008 Queen's Club Championships against Rafael Nadal in just over two hours. Facing the world No. 2, Nishikori played well in the match and showed promise. His first Grand Slam appearance at the 2008 Wimbledon Championships on 23 June 2008 ended in a first-round forfeiture to French player Marc Gicquel. Suffering from an abdominal muscle strain, Nishikori retired after the second set. In August, he entered the Beijing Olympics on a wildcard. There, he lost in the first round to Rainer Schüttler of Germany.

Nishikori made his debut at the US Open, defeating 29th seeded Juan Mónaco in the first round. He cruised to the third round, after downing Croatian Roko Karanušić. On 30 August 2008, he became the first Japanese player to reach the round of 16 at the US Open in 71 years, when he beat fourth seed David Ferrer in five sets in what was considered one of the tournament's major upsets. He lost his chance, however, to compete in the quarterfinals when he was beaten by 17th seed Juan Martín del Potro in straight sets.

Nishikori made a disappointing start to the season, losing to Jürgen Melzer in the first round of the Australian Open. On 25 March, Nishikori was named 2008 ATP Newcomer of the Year and became the first Asian player to win the award. He withdrew from the French Open, Wimbledon, and the US Open because of an injured right elbow.

Nishikori made his Davis Cup debut for Japan in April 2008 in the Asia/Oceania Zone Group I semifinal against India in New Delhi. He was 18 years and 104 days old, the youngest player to play for Japan. He played the singles rubber on the first day, but lost to Rohan Bopanna in five sets. He then defeated Mahesh Bhupathi in a dead rubber to record his first Davis Cup match win. To date, Nishikori has compiled a 19–3 win/loss record overall (17–3 in singles and 2–0 in doubles).

Nishikori represented Japan at his maiden Olympics in Beijing 2008. He competed in the singles competition from ITF places spot. There, he lost in the first round to Rainer Schüttler of Germany in three sets.

Nishikori won the 2004 title at the Riad 21 Tournament in Rabat, Morocco, and was a boys' singles quarter-finalist at the 2006 Junior French Open; he partnering Emiliano Massa to win the boys' doubles title at that tournament. Nishikori won the 2007 Luxilon Cup held at the 2007 Sony Ericsson Open by defeating Michael McClune.

Nishikori was born in Matsue in Shimane Prefecture, Japan. His father, Kiyoshi, is an engineer, and his mother, Eri, is a piano teacher. He has an older sister, Reina, who graduated from college and works in Tokyo. He began playing tennis at the age of five. He first won the All Japan Tennis Championships for Kids in 2001, and graduated from Aomori-Yamada High School. Nishikori moved to Bradenton, Florida to join the IMG Academy in 2004 at 14 years of age. His pastimes include football, golf, reading, and listening to music. Nishikori was previously coached by Brad Gilbert. Dante Bottini is his current coach since December 2010. Former world No. 2 Michael Chang was added to his coaching team from January 2014.

At the Australian Open, Nishikori was seeded eighth. In the first round, he faced qualifier Kamil Majchrzak, who was making his Grand Slam main draw debut. Majchrzak took the first two sets in just 90 minutes, before suffering from cramps. Nishikori won 15 of the next 17 games, before Majchrzak retired down 3 games to none in the fifth set. In the second round, he faced Ivo Karlovic, against whom he took the first two sets before dropping the third and fourth. The fifth set proceeded to a tiebreak, which Nishikori won 10-7. In the fourth round, he faced 23rd seed Pablo Carreño Busta. He dropped the first two sets before staging a major comeback, winning the third and fourth and leading by a break in the fifth before failing to serve out the match. Nishikori narrowly forced a tiebreak, trailing until a crucial point at 8-5, in which Busta contested an incorrect late call. The umpire awarded the point to Nishikori, who proceeded to win the tiebreak 10-8. He thus advanced to his fourth Australian Open quarterfinal, where he retired in the second set against Novak Djokovic.

Kei Nishikori (錦織 圭 , Nishikori Kei, [ɲiɕikoꜜɾi kei] ; born 29 December 1989) is a Japanese professional tennis player. He is the only male Japanese tennis player in history to be ranked inside the top 5 in singles, and first reached his career-high singles ranking of world No. 4 in March 2015. He is currently ranked world No. 31 by the Association of Tennis Professionals (ATP).

After his ATP main draw debut in Los Angeles, Nishikori qualified for the Indianapolis Tennis Championships in July. He beat Alejandro Falla in the first round to record his first ATP main-draw win. He followed that up with a three-set win over Michael Berrer, the eliminator of seventh seed Robby Ginepri, to advance to his first ATP quarterfinal. Although he lost to Dmitry Tursunov in two sets, Nishikori became the youngest player to reach the quarterfinals at Indianapolis since Boris Becker in 1985.