On Mike & Mike, Ian Fitzsimmons and Mike Golic react to Broncos SS David Bruton Jr. playing Sunday's game against the Steelers with a fractured right fibula. (1:11)

ENGLEWOOD, Colo. -- The Denver Broncos' depth at safety took another hit Monday when David Bruton Jr. was diagnosed with a fractured right fibula, an injury he played with for most of Sunday's game against the Pittsburgh Steelers.

Broncos coach Gary Kubiak said Bruton suffered the injury when Bruton collided with Broncos cornerback Aqib Talib on the defense's 15th play from scrimmage in the 34-27 loss at Pittsburgh on Sunday -- there was 1 minute, 58 seconds left in the first quarter when the play started.

"Played the entire game, amazing gut check,'' Kubiak said. " ... Obviously David's going to miss some extensive time here and we'll how that plays in with the remainder of the season.''

Bruton was on crutches in the locker room Monday. On Tuesday, he was placed on season-ending injured reserve.

"I thought it was a bruise,'' Bruton said. "There was a sharp pain initially and it just got worse and worse throughout the game.''

Just two plays after he suffered the fractured leg, Bruton also took a postplay helmet-to-helmet hit from Steelers center Cody Wallace after a 12-yard pass from Ben Roethlisberger to Antonio Brown. Bruton was slow to get up and the game was stopped by the medical spotter so Bruton could be taken to the sideline and evaluated by the Broncos' medical staff.

Wallace was penalized for unnecessary roughness and is expected to face a fine.

On Monday, Bruton called the hit "dirty'' and said Wallace "left his feet, trying to take me out.''

The collision that broke Bruton's leg happened on an incomplete pass from Roethlisberger to Martavis Bryant. Bruton was briefly tended to on the sideline, but he went on to play 77 snaps on defense, most of any Broncos player in the game. He added 18 more snaps on special teams.

Following the game, Bruton was helped to the locker room by linebacker Danny Trevathan and a team trainer. He was limping badly on his right leg. If the Broncos put Bruton on injured reserve, his season would be over.

David Bruton Jr. was lauded by Broncos coach Gary Kubiak for his toughness after he played most of Sunday's game with a fractured fibula. Rich Graessle/Icon Sportswire

Bruton had also been treated for a left knee injury in the days leading up to Sunday's game. The Broncos had two safeties -- T.J. Ward and Darian Stewart -- among their inactives Sunday. Both players are question marks for next Monday's game against Cincinnati.

Bruton said he was told the recovery time for his injury was approximately four to six weeks.

"But they told me my knee was two to four weeks and I was out 11 days,'' he said.

The Broncos worked Stewart out before Sunday's game to see the progress of his hamstring injury and elected to hold him out. Kubiak said he was hopeful Stewart would return to practice this week.

Ward, too, could possibly return to practice this week. He has missed the last three games with a left ankle injury he suffered in the Broncos' Nov. 29 victory over the New England Patriots.

Ward worked off to the side during practice last week, with the Broncos' strength and conditioning coaches.

In Sunday's loss, Josh Bush, who was signed Dec. 1, finished with an interception and played 61 plays on defense Sunday. Shiloh Keo, who was signed Dec. 9, played 37 plays on defense against the Steelers to go with 20 snaps on special teams.

"I thought Josh was exceptional, he was very sick before the game,'' Kubiak said. "I didn't know if he was going to make it to kickoff ... He's been with us three weeks, Keo's been with us two weeks ... and those guys continue to step up.''