A 6’0, 215-pounder who played at San Antonio Reagan, Sthele was ranked as the No. 140 player overall and the No. 47 right-handed pitcher in his recruiting class, according to Perfect Game.
Sthele immediately dealt with adversity after arriving on the Forty Acres, missing the 2021 season after undergoing surgery. When Sthele returned in 2022, he made three starts in 21 appearances, posting a 6.03 ERA and 32 strikeouts in 34.1 innings pitched while dealing with command issues. The inability to consistently throw strikes hurt Sthele again in 2023 when he started out in the weekend rotation before moving back to the bullpen, starting in 10 of his 15 appearances with a 5.75 ERA and 66 strikeouts in 61.0 innings. After hitting six batters in 2022, Sthele hit five in 2023 and had six wild pitches.