Pittsburgh Steelers pass rusher T.J. Watt underwent surgery Thursday to stabilize and repair a partially collapsed lung suffered after treatment at the Steelers’ facility on Wednesday, his brother, J.J. Watt, said Friday in a social media post.

T.J. Watt’s recovery timeline remains to be determined, but the All-Pro defender is being released from the hospital on Friday, J.J. Watt added.

“He and his family are very appreciative of everyone’s kind words and well wishes,” J.J. continued.

The Steelers star suffered the partially collapsed lung after a “dry needling treatment session,” J.J. said.

T.J. Watt is expected to play again this season, NFL Network Insider Ian Rapoport reported Friday, per sources. The Steelers have four games remaining in the regular season.

Coach Mike Tomlin told reporters after Friday’s practice that Watt was out of the hospital after Thursday’s procedure but will not play Monday against the Dolphins.