The Boston Red Sox have placed Joe Kelly on the disabled list with a shoulder impingement.

Kelly didn't feel right leading up to Tuesday night's start against the Tampa Bay Rays. He didn't say anything, believing he could push through the soreness that developed into a pinching sensation.

The right-hander walked off the mound with athletic trainer Brad Pearson with two outs in the first inning of Boston's 10-inning, 3-0 loss. He will be placed on the 15-day disabled list Wednesday but could miss considerably more time.

"It's really, really frustrating," Kelly said. "After I came out, I sat on my chair and ... it was something going through my head, pondering about what the next step is."