Tampa Bay Rays right-hander Jeff Niemann will be sidelined indefinitely after a test revealed inflammation in his shoulder, reports Marc Topkin of the Tampa Bay Times:

Rays RHP Jeff Niemann will be out indefinitely after an exam by Dr. Koco Eaton found slight inflammation in his rotator cuff.

It is unclear if he will pitch again this season.

Niemann, who missed nearly four months recovering from a broken leg, left his first start back on Saturday after three and a third innings because of "tightness" in his throwing arm. The 29-year-old right-hander expressed great frustration at his injury, but is hopeful the inflammation will subside in a few days time.

The Rays have pitched very well without Niemann in the rotation this season so surviving a bit longer without him probably will not hurt the club, but he could have added rotational depth in the final push for the playoffs. Niemann has made just eight starts on the season, posting a 3.08 ERA and 8.1 K/9 in thirty-eight innings.