Sean Guenther, a five-foot-11 left handed pitcher from Atlanta, GA, was taken by the Marlins in the seventh round of the 2017 MLB Amateur Entry Draft. In three seasons with the Notre Dame Fighting Irish, he was 6-14 with a 3.51 ERA and 153 strikeouts in 182 1/3 innings.
Despite concerns about Guenther’s height and middling 1.33 collegiate WHIP, Miami obviously saw something they liked. In his first four professional games, including three starts for the Rookie-level GCL Marlins in the Gulf Coast League, he allowed five hits in 11 innings, with 11 strikeouts, one run allowed, and a 0.