Padres' $3.4 Million Prospect Exits Start With Shoulder Injury

A moment later, an athletic trainer was on the mound chatting with Mayfield. After a brief discussion, Mayfield was removed from the game. Johan Moreno replaced him on the mound and was the losing pitcher in a 12-3 rout.

Any game-ending injury is a serious one. Fortunately, it appears Mayfield avoided a dire ailment. According to Jeff Sanders of the San Diego Union-Tribune, Mayfield was diagnosed with left shoulder discomfort.

The abrupt ending spoiled what was shaping into an encouraging start for Mayfield, who brought a 5.12 ERA into the game. The California League is a hitter's paradise, and Mayfield's 27-to-9 strikeout-to-walk ratio this season and 1.279 WHIP suggest he's acclimating well for a 20-year-old.

The Padres drafted Mayfield 25th overall out of Elk City (Okla.) High School — one pick after the Braves selected Cam Caminiti, the cousin of former National League MVP and Padres star Ken Caminiti.

Mayfield was assigned to pitch in the Arizona Complex League after he was drafted, but he did not log an inning in the ACL season. His first month with Lake Elsinore was his first as a professional.

Although no timetable has been given for Mayfield's return, don't be surprised if the organization treats even a minor injury to one of its top prospects with caution. Mayfield is ranked as the No. 3 prospect in the Padres organization by MLB Pipeline, behind only Top-100 talents Leo De Vries and Ethan Salas.

Mayfield, 6-foot-4 and 200 pounds, boasts a plus changeup and outstanding control. He received a $3.4 million signing bonus, the assigned slot value for the No. 25 pick in last year's draft.

MLB.com projects Mayfield's major league arrival for 2028.

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