Parker joins the Gamecocks after spending three seasons as the associate head coach/pitching coach at Indiana University. His staff with the Hoosiers had a 3.17 ERA and struck out 462 batters in 383.1 innings pitched as Indiana went 26-18 with a Big Ten-only schedule in 2021. Four pitchers from Parker's staff were selected in the 2021 MLB Draft, including McCade Brown, who was selected in the third round by the Colorado Rockies and Gabe Bierman, picked in the seventh round by the Miami Marlins.
Parker has consistently produced pitchers selected in the MLB Draft. Of his 20 draft picks, nine have gone in the first 10 rounds.
In the shortened 2020 season, Parker helped lead the Hoosiers to a 9-6 record overall, beating No. 11 LSU, No. 30 South Alabama and No. 17 East Carolina. On the mound, the Hoosiers posted a team ERA of 3.56, striking out 134 batters in 129.0 innings pitched. In 2019, Parker help guide the Hoosiers to the 2019 Big Ten Regular-Season title – the seventh in program history and the first for IU since 2014. Indiana earned a No. 2 seed in the NCAA Tournament, finishing the season with an overall record of 37-23 and a Big Ten mark of 17-7. A school-record 10 Hoosiers were selected in the 2019 MLB Draft, led by outfield Matt Gorski, who was selected in the second round (57th overall).
Prior to joining the Hoosiers, Parker served as the pitching coach at UCF for two seasons. During the 2018 campaign at UCF, Parker's staff posted a 3.32 ERA, the eighth sub-3.50 ERA season in school history. Pitchers struck out 556 batters, good for second in program history behind 2001's 597, while the Knights set a new program record with 7.1 hits allowed per nine innings and gave up the third-fewest hits at 405. Under Parker in his first season with the Knights in 2017, the pitching staff was one of the best in the nation, finishing 10th in WHIP (1.22), 24th in strikeout-to-walks ratio (2.74), 28th in strikeouts per nine innings (8.9) and 52nd in walks per nine innings (3.26). The crowning achievement for Parker's players was the fifth-best ERA in the nation at 3.00.