OAKLAND -- Daulton Jefferies' young career is on hold, after the A's pitching prospect learned Thursday he needs season-ending Tommy John surgery.
According to A's general manager David Forst, who confirmed the news, it has not yet been decided who will perform the procedure, which typically requires a minimum of 14 months of recovery time.
The right-handed Jefferies, ranked by MLBPipeline.com as the organization's No. 8 prospect, was a second-round Draft pick of the A's just last year. The Cal Berkeley product made two appearances for Class A Stockton this season, tossing four scoreless innings in his debut before allowing six runs (two earned) in his next outing.
Jefferies, 21, was limited to 50 innings during his final season at Cal because of injuries, none involving his elbow.
Jane Lee has covered the A's for MLB.com since 2010. This story was not subject to the approval of Major League Baseball or its clubs.