He went undrafted in the 2015 Major League Baseball draft, and enrolled at Wichita State University where he played college baseball for the Shockers.[4] In 2016, his freshman season at Wichita State, he appeared in 21 games (making two starts) in which he went 1–1 with a 9.12 ERA in 24+2⁄3 innings,[5] and as a sophomore in 2017, he pitched to a 2–2 record and 4.42 ERA in 38+2⁄3 innings.[6] In 2018, his junior year, he was Wichita State's Friday night starter, going 6–5 with a 4.31 ERA over 16 games (15 starts).[7][8]
Professional career
Chicago White Sox
After his junior year, Heuer was selected by the Chicago White Sox in the sixth round of the 2018 Major League Baseball draft.[9] He signed and made his professional debut with the Great Falls Voyagers.[10] He made 14 starts, going 0–1 with a 4.74 ERA over 38 innings, as the Voyagers won the Pioneer League crown.[11] In 2019, he moved to the bullpen, and began the year with the Winston-Salem Dash before being promoted to the Birmingham Barons in June.[12] Over 42 relief appearances between the two clubs, Heuer went 6–4 with a 2.39 ERA, striking out 65 over 67+2⁄3 innings.[13]
On July 23, 2020, it was announced that Heuer had been named to the White Sox 2020 Opening Day roster.[14] He made his MLB debut the next night against the Minnesota Twins, striking out one and pitching a scoreless inning.[15][16] With the 2020 Chicago White Sox, Heuer appeared in 21 games, compiling a 3-0 record with 1.52 ERA and 25 strikeouts in 23+2⁄3 innings pitched.[17] For the 2021 White Sox, Heuer went 4-1 with a 5.12 ERA and 39 strikeouts over 38+2⁄3 innings.[18]
Chicago Cubs
On July 30, 2021, Heuer was traded along with Nick Madrigal to the Chicago Cubs for Craig Kimbrel.[19] Heuer appeared in 25 games for the Cubs in which he went 3-3 with a 3.14 ERA and 17 strikeouts over 28+2⁄3 innings.[20] On March 8, 2022, Heuer underwent Tommy John surgery, ending his 2022 season before it began.[21][22]
On January 13, 2023, Heuer agreed to a one-year, $785,000 contract with the Cubs, avoiding salary arbitration.[23] After 15 rehab appearances for the Triple–A Iowa Cubs, it was announced on June 24 that Heuer would undergo season–ending surgery to address an elbow fracture he had suffered earlier in the week.[24] He was non-tendered and became a free agent on November 17.
Texas Rangers
On April 6, 2024, Heuer signed a minor league contract with the Texas Rangers.[25] He returned to action in 2025 with the Triple-A Round Rock Express, posting a 2-1 record and 3.27 ERA with 25 strikeouts across 19 appearances.
On June 1, 2025, Texas selected Heuer’s contract and added him to their major league roster.[26]
Detroit Tigers
On July 31, 2025, Heuer was traded to the Detroit Tigers, for cash considerations.[27][28]
