Harrison was drafted by the Milwaukee Brewers in the second round of the 2014 Major League Baseball draft.[10] He signed with the Brewers on June 14[11] and was assigned to the Arizona League Brewers where he posted a .261 batting average with one home run and 20 runs batted in, along with 32 stolen bases, in 50 games.
In 2015, Harrison began the season with the Wisconsin Timber Rattlers, and after batting .148 with 11 runs batted in during 46 games, he was reassigned to the Helena Brewers, where he finished the season with a .299 average with three home runs and 13 runs batted in during 28 games. In 2016, Harrison returned to the Timber Rattlers and spent the whole season there, playing in 75 games, batting .221 with six home runs and 37 runs batted in.[12] He spent the 2017 season with both Wisconsin and the Carolina Mudcats and posted a combined .272 batting average with 21 home runs, 67 runs batted in, and 27 stolen bases in 122 games between both clubs.[13]
Harrison was promoted to the major leagues on August 3, 2020,[19] and made his MLB debut the next day.[20] In 32 games for Miami, he hit .170 with one home run and three runs batted in.[21] Harrison also made his postseason debut that year with the Marlins against the Chicago Cubs in the 2020 National League Wild Card Series, where he pinch-ran and had one stolen base.[22]
To begin the 2021 MLB season, Harrison was placed at the Marlins alternate training site.[23] On April 30, Harrison was called up by the Marlins. Harrison went 1-for-5 in three games for the Marlins before being sent down on May 4 to Triple-A Jacksonville.[24]
On March 18, 2022, Harrison was designated for assignment by Miami.[25] He was released by the team on March 26.[26]
Los Angeles Angels
On April 5, 2022, Harrison signed a minor league contract with the Los Angeles Angels organization.[27] He was promoted to the major league roster on June 24 after Juan Lagares was designated for assignment.[28] On July 13, the Angels designated Harrison for assignment. He cleared waivers and was sent outright to the Triple-A Salt Lake Bees on July 18.[29] On October 12, Harrison elected free agency.
Milwaukee Brewers (second stint)
On January 30, 2023, Harrison signed a minor league contract with the Milwaukee Brewers organization.[30] In 88 games for the Triple-A Nashville Sounds, he batted .208/.277/.316 with 5 home runs, 23 runs batted in, and 18 stolen bases. On September 24, Harrison was released by Milwaukee.[31]
Despite committing to Nebraska out of high school, Harrison did not use any eligibility as a football player as he instead opted to play professional baseball after the Milwaukee Brewers drafted him in 2014. On May 7, 2024, nearly 10 years later, he committed to play football for the University of Arkansas, set to join the Razorbacks as a walk-on beginning with the 2024 season.[32]
Personal
His brother, Shaquille Harrison, is a professional basketball player in the NBA.[33] Harrison's father, Jack, died due to a heart attack when he was in first grade.[34]