Rays' Niemann headed for surgery

Tampa Bay Rays pitcher Jeff Niemann will undergo shoulder surgery on Wednesday that will likely sideline him for the entire 2013 season.

Niemann had been experiencing shoulder soreness all throughout spring training, and a recent examination revealed abnormalties in his labrum and rotator cuff, according to MLB.com.

The 6-foot-9 righty had been slated to work as a long reliever this season after losing a battle with offseason pickup Roberto Hernandez for the Rays' final rotation spot in the spring. He was placed on the disabled list on Friday.

Niemann posted a 36-21 record from 2009-11, his first three full major league seasons, but made just eight starts last year due to a fractured right fibula and shoulder issues. He went 2-3 with a 3.08 earned run average.