Aaron Bummer

Chicago selected Bummer's contract on July 27, 2017, and he made his Major League debut that same night against the Chicago Cubs, striking out the first batter he faced, Anthony Rizzo. In 49 innings pitched between Winston-Salem, Birmingham and Charlotte prior to his call up, he was 1-5 with a 3.31 ERA. Bummer spent the remainder of 2017 with the White Sox, compiling a 1-3 record and 4.50 ERA in thirty relief appearances. In 2018, Bummer made 37 appearances, collecting an ERA of 4.26 in ​31  ⁄3 innings. The following season, he improved dramatically, registering an ERA of 2.13 in ​67  ⁄3 innings.

After signing with the White Sox, Bummer made his professional debut that same year with the Great Falls Voyagers where he compiled a 2.45 ERA in 22 innings pitched. He missed all of 2015 due to injury. In 2016, he pitched for the Arizona League White Sox, Great Falls, and Winston-Salem Dash where he was a combined 1-2 with a 4.86 ERA in 15 relief appearances between the two teams. He began 2017 with Winston-Salem, was promoted to the Birmingham Barons in May, and was promoted to the Charlotte Knights in July.

Bummer attended Sunrise Mountain High School in Peoria, Arizona and was drafted by the New York Yankees in the 31st round of the 2011 MLB draft. He did not sign and played college baseball the University of Nebraska–Lincoln. In 2013, he played collegiate summer baseball with the Harwich Mariners of the Cape Cod Baseball League, and was named a league all-star. In 2014, as a junior at Nebraska, he went 7-5 with a 3.34 ERA in 15 starts. After the season, he was drafted by the Chicago White Sox in the 19th round of the 2014 MLB draft.

Aaron James Bummer (born September 21, 1993) is an American professional baseball pitcher for the Chicago White Sox of Major League Baseball (MLB).