KANSAS CITY, Mo. (AP) Royals pitching prospect Kyle Zimmer had surgery on his shoulder to remove damaged tissue, throwing his status for the start of next season into question.
Tuesday's surgery was performed by New York Mets medical director Dr. David Altchek in New York.
The Royals had hoped the 23-year-old Zimmer would be able to help them this season, but a series of injuries have curtailed his development. He was shut down in May with a lat injury.
Zimmer, a first-round pick in 2012, made just six appearances at rookie-league Idaho Falls in August and September. He had a 1.93 ERA with five strikeouts in 4 2-3 innings.
He also made three starts in the Arizona Fall League before getting shut down.