PITTSBURGH -- The Steelers on Friday placed veteran kicker Chris Boswell on injured reserve and signed tryout kicker Matt McCrane.

Boswell's injury is unknown, but a source told ESPN that Boswell is dealing with a lower-body injury. He didn't appear on the injury report for Week 17 against the Cincinnati Bengals.

Boswell experienced discomfort after Sunday's loss to the New Orleans Saints, and Steelers coach Mike Tomlin waited until after Thursday's practice, Boswell's usual kicking day during the week, to see how he responded.

Boswell was still having issues after that session.

"We felt it was necessary to make the move," Tomlin said. "We had worked Matt out a number of weeks ago, so it was a matter of a quick phone call."

Pittsburgh tried out McCrane and veteran Kai Forbath in Week 15 after two Boswell misses cost the Steelers during a loss in Oakland, but the team stuck with Boswell after a productive practice.

Boswell told ESPN on Thursday that he hoped he had turned the corner after three straight makes, but he added that things can always "go south" so he had to stay confident regardless.

Boswell, a Pro Bowl kicker last season who signed a five-year, $20 million extension in August, made 13 of 20 field goal attempts and 43 of 48 extra point attempts this season.

McCrane went 5-for-9 on field goals for Oakland earlier this year.