TheLos Angeles Dodgers selected Ginn with the 30th overall selection of the2018 MLB draft.[6] On July 5, 2018, he announced that he was going to honor his commitment to Mississippi State and that he would not be signing with the Dodgers.[7][8] In 2019, his freshman year at Mississippi State, he went 8–4 with a 3.36 ERA over 16 starts, striking out 103 over eighty innings.[9] He was named the 2019Southeastern Conference Freshman of the Year.[10] He underwentTommy John surgery in March 2020.[11]
Ginn was selected 52nd overall by theNew York Mets in the2020 MLB draft.[12] He signed with the Mets on June 30, 2020, for a $2.9MM bonus.[13] He did not play a minor league game in 2020 due to the cancellation of the minor league season caused by theCOVID-19 pandemic alongside still recovering from surgery.[14] Ginn returned to play in June 2021, making his professional debut with theSt. Lucie Mets of theLow-A Southeast.[15] He was promoted to theBrooklyn Cyclones of theHigh-A East in July.[16] Over 18 starts between the two teams, Ginn went 5–5 with a 3.03 ERA and 81 strikeouts over 92 innings.[17]
On March 12, 2022, the Mets traded Ginn andAdam Oller to theOakland Athletics in exchange forChris Bassitt.[18] He opened the season with theMidland RockHounds of theDouble–ATexas League.[19] In 12 starts split between Midland and the rookie–levelArizona Complex League Athletics, Ginn compiled a 1–4 record and 5.10 ERA with 46 strikeouts across42+1⁄3 innings pitched.[20] He returned to the two affiliates in 2023, making 8 starts and struggling to a 7.43 ERA with 17 strikeouts over26+2⁄3 innings of work.[21]
Ginn began the 2024 season with Midland, logging a 4–1 record and 4.15 ERA over 6 starts. In May, he was promoted to the Triple–ALas Vegas Aviators, for whom he logged a 4–3 record and 5.72 ERA with 69 strikeouts across 15 games (14 starts). On August 20, 2024, Ginn was selected to the40-man roster and promoted to the major leagues for the first time.[22] In 8 games (6 starts) for Oakland during his rookie campaign, Ginn posted a 1-1 record and 4.24 ERA with 29 strikeouts across 34 innings pitched.
Ginn was optioned to Triple-A Las Vegas to begin the 2025 season.[23]