Denver Broncos linebacker Wesley Woodyard sacks Cleveland Browns quarterback Colt McCoy in the fourth quarter at Sports Authority Field at Mile High on Sunday, December 23, 2012, in Denver, Colorado. The Denver Broncos defeated the Cleveland Browns, 34-12.

(Photo by Mark Reis/Colorado Springs Gazette/MCT)

BEREA, Ohio -- Brandon Weeden wasn't the only Browns quarterback who flew home from Denver on Sunday night with a bad wing.

Colt McCoy, who replaced Weeden with 3:54 left in the third quarter, suffered the same fate -- a sprained shoulder on a sack. As a result, practice-squad call-up Thad Lewis might have to make his NFL regular-season debut as the starter in Sunday's season finale in Pittsburgh.

The Browns also signed fifth-year quarterback Josh Johnson, who will serve as Lewis' backup in Pittsburgh if Weeden and McCoy can't play.

McCoy and Weeden were idle Wednesday, and Lewis took all the first-team reps.

Browns coach Pat Shurmur has yet to rule out either of the two injured quarterbacks, or injured running back Trent Richardson, who suffered a sprained left ankle on the second-to-last play of the game when McCoy fell on it.

The Browns breathed a sigh of relief this week that the injuries weren't as serious as originally feared. Richardson's was of particular concern because he has screws in both ankles to keep the ligaments intact.

Richardson, who was carted off the field and hobbled to the team bus in a walking boot Sunday, hopes to play against Pittsburgh, in part, because he's only 50 yards from 1,000 for the season. If he can't play, Montario Hardesty will start in his place.

The injuries to McCoy and Richardson on the final drive caused a stir among several Browns players, who were miffed that the team used three timeouts on the previous drive instead of letting the clock run down. Trailing, 34-12, and with less than two minutes remaining, the Browns passed on every play and kept Richardson in to block. The Broncos' fearsome pass-rushers attacked relentlessly.

Shurmur defended the strategy Monday, saying he was still competing and that all the starters were in. Weeden, Richardson and McCoy weren't available for comment Wednesday.

Shurmur has faith in Lewis, whom he coached in St. Louis.

"I've had experience with Thad in the past," he said. "He hasn't had a lot of opportunity in regular-season games to go in there and play, but if he's in there playing, we definitely trust that he'll do a good job."

Lewis (6-2, 200) signed with the St. Louis Rams as an undrafted free agent out of Duke in 2010 and spent the final 16 weeks of the season on the practice squad. The Browns claimed him off waivers in September 2011, and he was inactive for most of the season. This season, he made the roster out of camp but was waived Oct. 11 and signed to the practice squad two days later.

"If I get the start, it'll be wonderful," Lewis said. "It'll be like living out a childhood dream. Right now, I'm just taking it all in and enjoying it while I can in practice, taking the reps. If my number does get called, it will be amazing."

Lewis was reminded that McCoy was thrown into the fire under similar circumstances, when he had to start in Pittsburgh as a rookie in 2010 with no reps due to injuries. The Browns lost, 28-10, but McCoy held his own in the face of the Steelers' zone blitzing.

"No, I didn't talk to him about it, but now that you mention it, I'll make sure I'll do it since he has experience," Lewis said. "But those guys have been supportive. They're saying, 'Go out there and practice and just do the things you know how to do.' That's what you look for in a teammate."

Lewis wouldn't classify it as a baptism by fire.

"No, I'd just say it's a challenge," he said. "Every week, any team could beat a No. 1 defense. But just because you're facing a No. 1 defense, you've just got to go out there and do the things that you're coached to do, make the right decisions and let the guys help you out, no matter what team it is. If it wasn't Pittsburgh, it was a different team, it would be the same process going into it."

Johnson (6-3, 205), who ran the scout team Wednesday, was Tampa Bay's fifth-round draft pick out of the University of San Diego in 2005. He spent four seasons in Tampa Bay, losing all five of his starts, with five touchdowns and 10 interceptions.