BEREA: When Browns third-string quarterback Thaddeus Lewis would visualize his debut as an NFL starter, he never pictured lining up across from linebacker James Harrison, safety Troy Polamalu and the rest of the Pittsburgh Steelers’ No. 1-ranked defense amid Terrible Towel-waving fans at Heinz Field.

But that’s exactly what Lewis will do Sunday when the Browns (5-10) visit the Steelers (7-8). He will become the Browns’ 18th starting quarterback since their expansion era began in 1999 because Brandon Weeden and Colt McCoy have been officially ruled out with injured throwing shoulders. Josh Johnson, whom the Browns recently signed off the street, will serve as Lewis’ backup.

“Part of my childhood dream was to be a starter one day in the NFL,” Lewis said. “Who it was against, I didn’t have a visual of that. But it’s a challenge, and if you don’t like challenges, then you’re in the wrong sport.”

Lewis won’t receive any assistance from rookie running back Trent Richardson, who was ruled out with a sprained left ankle. Like Weeden and McCoy, Richardson did not practice this week after getting hurt Sunday in the Browns’ 34-12 loss to the Denver Broncos.

Montario Hardesty will start in place of Richardson, and Brandon Jackson will serve as his backup. Fellow running back Chris Ogbonnaya will also play, coach Pat Shurmur said.

“I just have to make sure I make the most out of my opportunity on the field and just go out and play a good game and go out and show people what I can do,” said Hardesty, a second-round pick in the 2010 draft who has been hindered by knee and calf injuries in the past two years. “I still feel like there’s a lot of stuff that I haven’t shown yet in the NFL that I want to show.”

Hardesty has 51 carries for 234 yards (4.6 average) and a touchdown this season. He has played in 11 games this season.

On the other hand, Lewis has never appeared in an NFL regular-season game, spending most of the past three seasons on the practice squads of the Browns and the St. Louis Rams.

“He’s had a good week of practice,” Shurmur said of Lewis, who entered the league as an undrafted free agent from Duke University. “He’s been preparing himself to play all year even though he wasn’t on the active roster.”

Weeden’s rookie season will end one game short of the finish line. Tim Couch is the last Browns quarterback to play all 16 games. He did it in 2001.

Weeden set a franchise rookie record by passing for 3,385 yards, and he threw for 14 touchdowns. But he also finished with 17 interceptions and a passer rating of 72.6, which is the third worst in the league.

“Now that he’s had a season under his belt, he’ll [be] much like a lot of quarterbacks in this league that went on to have really good careers,” Shurmur said. “Just pick one. They all had rookie years where they were much better in their second year. I think he’s shown quite a bit this year that’s good.”

As for Lewis, he knows the Steelers haven’t been kind to Browns quarterbacks in recent years. McCoy suffered a season-ending concussion when he absorbed a helmet-to-face mask hit from Harrison on Dec. 8, 2011.

“If you get hit, that’s what the pads [are] for — to protect you,” Lewis said when asked if he’s worried about Harrison. “You’ve got to be tough at the quarterback position. You’ve got to get up, shake it off and move on to the next play.”

The last time the Browns played a season finale at Heinz Field was Dec. 28, 2008, when fourth-string quarterback Bruce Gradkowski was summoned to start. He completed 5-of-16 passes for 18 yards with two interceptions in a 31-0 loss. He also took three sacks and had a passer rating of 1.0.

The Browns, though, believe Lewis will avoid a disaster. They’re 5-23 against the Steelers since 1999 but have a chance to earn a season sweep in the series for the first time since 1988 after prevailing 20-14 on Nov. 25.

“Thad has displayed everything that he needs to, to prove himself and to go out and have a great showing on Sunday,” wide receiver Greg Little said. “He’s obviously in the NFL for a reason. He has a great talent and his overall understanding of the offense is tremendous.”

Streak snapped

Cornerback Sheldon Brown’s streak of 175 consecutive regular-season games played will end. He was ruled out for Sunday with a concussion he suffered against the Broncos. It’s the second-longest streak among active NFL defensive backs.

“If I were sitting in his shoes, it would be hard to watch because I’d be so overcome with emotions,” Pro Bowl left tackle Joe Thomas said. “It would be just too much. If he does watch, I wouldn’t be surprised if he cries.”

Brown, who’s in his 11th NFL season, might have played his final game with the Browns because he’s scheduled to become a free agent in March.

“It’s killing him,” middle linebacker D’Qwell Jackson said. … “I just feel bad for him. I know he wants to play.”

Second-year cornerback Buster Skrine will start in place of Brown. Rookie Trevin Wade will serve as the nickel corner.

More opportunities

Brandon Jackson missed all of last season with an injured toe and has only played in one game this season. He’s hungry for a chance to play Sunday.

“It’s been tough,” said Jackson, who signed with the Browns last year after spending four seasons with the Green Bay Packers. “Through my faith and my wife and my kids, I’ve been strong. That’s all I can really rely on at that point in time. Now I get the opportunity to go out and show the team what they’ve been missing.”

Tight end Jordan Cameron was also ruled out with a concussion. Rookie Brad Smelley and veteran Alex Smith should receive more playing time as a result.

Extra points

Don Banks of Sports Illustrated wrote that David Caldwell, the Atlanta Falcons’ director of player personnel, is a general manager candidate to keep an eye on if the Browns part with GM Tom Heckert. … The Browns listed defensive tackle Ishmaa’ily Kitchen (calf) as questionable on their injury report. Eight others are probable. … The Steelers ruled out offensive tackle Mike Adams (ankle), cornerback Curtis Brown (ankle), linebacker Marshall McFadden (abdomen) and wide receiver Mike Wallace (hip). Three others are probable. … Undrafted rookie safety Jordan Mabin, a Nordonia High School graduate, was thrilled when the Browns recently signed him to their practice squad. “I’d live and die Cleveland Browns growing up,” said Mabin, a native of Northfield Center. “So when they called to say they wanted to bring me in, I was ecstatic.” … The Browns will play the Baltimore Ravens, Buffalo Bills, Chicago Bears, Cincinnati Bengals, Detroit Lions, Jacksonville Jaguars, Miami Dolphins and Steelers at home next season. They’ll face the Ravens, Bengals, Steelers, Green Bay Packers, Kansas City Chiefs, Minnesota Vikings, New England Patriots and New York Jets on the road in 2013.

Nate Ulrich can be reached at nulrich@thebeaconjournal.com. Read the Browns blog at https://ohio.com/browns. Follow him on Twitter at www.twitter.com/NateUlrichABJ and on Facebook www.facebook.com.browns.abj.