Robert Ghost

On November 8, 2018 Guerrero surprisingly announced he would be returning to the boxing ring, stating he had 'some fight left' and also wanting to further his legacy. According to ESPN, his return bout would take place on December 1 on the Wilder vs. Fury Showtime PPV card at the Staples Center in Los Angeles, California. Guerrero was scheduled to fight 27-year-old Hungarian boxer Adam Mate (28–12, 21 KOs) in a 10-round welterweight bout. For the comeback, Guerrero was guaranteed a $25,000 purse. Fighting for the first time in 16 months, Guerrero knocked out Mate in round 2 of their scheduled 8 round bout. Mate was knocked down once in round 1, taking a knee and twice in round 2. After beating the count for the second knockdown, referee Ray Corona stopped the fight. It was Guerrero's first stoppage win in 13 fights, dating back to April 2010.

On May 23, 2017 it was announced that Guerrero would fight at the renovated Nassau Coliseum in Uniondale, New York against undefeated former WBC lightweight champion Omar Figueroa Jr. (26–0–1, 18 KOs) on July 15, 2017. The bout will take place as part of a triple header main event which would include Sean Monaghan vs. Marcus Browne. Before this fight, Figueroa last fought in December 2015. The first boxing event to take place at the Coliseum in 31 years saw Guerrero stopped in the third round in front of a crowd of 7,492. Figueroa dropped Guerrero a total five times before the fight was halted. According to Compubox stats, Figueroa landed 88 of his 185 punches thrown (48%), whilst Guerrero landed 78 of 201 thrown (39%). Guerrero saw success in round 1, but the fight turned around when Figueroa landed a huge left hook knocking Guerrero down and eventually handing him his third consecutive loss. According to Nielsen Media, the fight peaked at 1,039,000 viewers on Fox. The whole show averaged 886,000 viewers.

On January 23, 2016 Guerrero fought on FOX as part of the "Premier Boxing Champions" series at Staples Center, California, against the undefeated Danny Garcia (31–0–0, 18 KO) for the vacant WBC Welterweight Championship. The match was ruled a unanimous decision in favor of Garcia with all three judges scoring the bout 116–112, despite fighting on near-equal terms. Guerrero started off impressive, but became less effective late in the fight falling to a 3rd career defeat in a welterweight title fight. Garcia landed 163 of 496 thrown (33%), whilst Guerrero landed 108 of 436 punches thrown (25%).

On June 6, 2015 Guerrero fought again on NBC as part of the "Premier Boxing Champions" series at StubHub Center, California, against the gritty Aron Martinez (19–4–1, 4 KOs). Martinez proved himself to be an underdog with bite. The action got going in earnest in Round 2, with both fighters working the body hard in some grueling infighting. Martinez continued to press the action in Round 4, scoring a knockdown at the end with hard body shots and then combinations to the head. But the momentum of the fight began to swing back in Guerrero's direction in Round 6, when he fought more from the outside. Both fighters had their moments in the latter half of the fight, but it was Guerrero who was able to control the distance, outland Martinez and pull out a split-decision win in a feisty back-and-forth battle.

Guerrero took off a full year before returning to the ring on June 21, 2014 to fight Japanese boxer Yoshihiro Kamegai. Guererro could hardly open his left eye toward the end of the fight, but scored a unanimous 12-round decision over the tough Kamegai with official scores of 116–112, 117–111, and 117–111, thereby marking a triumphant return to the ring.

Guerrero lost the belt in his next fight in a mandatory defense to future Featherweight champion Orlando Salido in Las Vegas. Salido dominated the majority of the bout and pulled off an upset decision win with scores of 115–113, 117–111, 118–110. However, Salido would subsequently be stripped of the IBF title after testing positive for steroids, thus vacating the belt; the result of the bout would also be changed to a twelve-round no decision by the Nevada State Athletic Commission.

Guerrero returned to the ring by jumping two weight classes to face unbeaten top 10 welterweight Selcuk Aydin. On July 28, 2012 Guerrero defeated Aydin in San Jose, California by unanimous decision for the interim WBC welterweight title.

On April 9, 2011, Guerrero faced Michael Katsidis for the interim WBA and WBO lightweight titles. Guerrero won the bout with a 12-round unanimous decision. In a post-fight interview when asked about his hometown he said, "It's nice when you're pretty much their biggest thing besides garlic in Gilroy." Guerrero was scheduled to face Marcos Maidana in August for the WBA junior welterweight title, however, he was forced to pull out of the bout after suffering a torn tendon in his rotator cuff. He underwent surgery to repair the injury and was out of the ring for 6 months.

In February 2010, Guerrero vacated his Featherweight title in order to care for his ailing wife.

On March 7, 2009, Guerrero fought Daud Yordan in his HBO debut. The fight ended in a second round "no contest" decision after Guerrero suffered a headbutt resulting in a gash above his eye. After the bout Guerrero offered Yordan a rematch, however, Yordan reportedly declined.

On February 29, 2008, Guerrero defeated Jason Litzau via an eighth round knock out. Guerrero then vacated the title to move up in weight.

The IBF subsequently gave Guerrero the shot at the vacant featherweight title, which he won by ninth-round technical knockout in Copenhagen, Denmark on February 23, 2007, against Albanian boxer Spend Abazi.

In his first world championship fight on September 2, 2006, Guerrero defeated Eric Aiken by an eighth-round technical knockout in Los Angeles. Guerrero used inside fighting, neutralizing Aiken's power, and eventually making Aiken quit on his stool after the eighth round to earn his first world title belt.

Guerrero is trained by his father Ruben Guerrero, a former amateur champion, who introduced Robert and his five brothers to boxing as youngsters growing up in Gilroy, California. After an impressive amateur career begun at a very young age, Robert turned professional, at the age of 18, on May 22, 2001 with a four-round unanimous decision win against Alejandro Cruz. After several wins and only a single draw later, Guerrero won the WBC NABF Featherweight title against Cesar Figueroa on December 9, 2004. Defending his NABF title twice, Guerrero was seen as a rising prospect, until meeting Gamaliel Diaz in a bout televised on ShoBox, on the Showtime channel, on December 12, 2005. An aggressive Diaz upset Guerrero, winning by split decision and taking the NABF belt in the process.

Robert Joseph Guerrero (born March 27, 1983) is an American professional boxer. He has held world championships in two weight classes, including the IBF featherweight title twice between 2006 and 2008, and the IBF junior lightweight title from 2009 to 2010. Additionally he has held multiple interim titles at lightweight and welterweight.

Robert Ghost was born on December 9, 1975 in Orlando, Florida, USA.