Sean Manaea, who has been the best starting pitcher for the Oakland Athletics, will have season-ending surgery on his left shoulder, the team announced Tuesday.
Manaea, who was 12-9 with a career-best 3.59 ERA and 108 strikeouts in 27 starts this season, will visit specialist Dr. Neal ElAttrache in Los Angeles to have the arthroscopic procedure on Sept. 19.
Manaea, 26, began strengthening exercises on Sept. 3, but the team felt it was best to have the surgery at this point.
When he was placed on the disabled list on Aug. 26 for rotator cuff tendinitis, Manaea was tied for second in the American League in games started, ninth in innings pitched and sixth in fewest walks per nine innings (1.