Last Friday, Washington Redskins left tackle Trent Williams looked nothing like a man with the ability to suit up and play effectively when his team visited the Tampa Bay Buccaneers on Sunday.

He would try to jog, but could only make it a few steps before he had to stop. He’d walk from point to point, dragging his right leg because of the bone bruise in his knee that he had suffered the week before.

Teammates said they expected to go without the former No. 4 overall pick of the 2010 draft — their most talented offensive lineman and the protector of Robert Griffin III’s blind side.

Sunday morning came, and Williams — who still limped noticeably in pregame warmups — started and didn’t miss a snap. Later, Coach Mike Shanahan said: “I thought it was his best game of the season.”

Williams said he wouldn’t have played through such pain in the past. But this season, he views every snap and positive play as paying an installment on the hefty debt he believes he owes the team and its fans for his four-game suspension at the end of last season. Williams was sanctioned after he failed multiple drug tests.

“That’s a driving force behind a lot of things that I do as of now,” Williams said this week. “I made a mistake, and I kind of use it as a learning experience. Of course, I alienated my team for four games and wasn’t able to be there. I was a captain at the time, and that made me feel even worse. This year I’m just trying to prove to them that I’ve grown up a lot and that’s not me anymore.”

Meanwhile, another Redskin with a debt to repay was playing well Sunday. Tight end Fred Davis, who also flunked multiple tests for marijuana use and was suspended for the final four games along with Williams, continued his journey back to redemption, with four receptions for 70 yards. His biggest play came on the game-winning drive, when, with 1:20 left on the clock, he caught the ball seven yards off the line and ran another 13 into Bucs’ territory.

It was the second consecutive impact game for Davis, who after a slow start in the first two weeks of the season, now ranks among the top 10 in tight ends with 212 receiving yards on 14 catches.

Together, Williams and Davis have earned back the trust of the franchise on and off the field.

“They’re two talented guys,” Griffin said. “No one can take that away from them. It was just about being accountable, just making sure they took care of business. They’ve done that.”

The NFL’s substance abuse program requires that Williams and Davis take drug tests several times a week, but Redskins’ coaches and players put the failed drug tests behind them long ago. The two sat down with Shanahan and, after lengthy talks, the coach knew they had learned their lessons.

This summer, Redskins players voted Williams the offensive captain and Davis their offensive player of the year.

“I don’t think people on my team are even thinking of last year,” said Davis, who was assigned the team’s franchise tag to keep him under contract an additional season. “They know what I’m going to do as far as that situation. It’s just a matter of keep playing and make as many plays as you can.”

Davis began his breakout last season. He recorded career highs in catches (59) and yards (796) and was on pace to set a franchise record for receiving yards by a tight end and post the first 1,000-yard season by a tight end in team history.

Washington brass had enough faith in Davis to release longtime Redskin Chris Cooley before the season. After playing in Cooley’s shadow for the better part of his career, Davis now is the featured tight end.

“This is really his chance to have the position by himself,” said veteran receiver Santana Moss. “Cooley has always been here with him and always did a tremendous job all of Fred’s years, and last year was when I saw the light click on and [Davis] came in lighter, started working out and training hard with that mentality that, ‘I want to be the best tight end.’ That carries over into this year, and now he knows that’s his job and position to lead us on the field.”

While Davis has shown his potential Pro Bowl form, Williams still must prove that he can live up to the expectations the Redskins had when they first drafted him. He trained hard in the offseason and reported for training camp in the best shape of his career, determined to redeem himself by helping to produce a winning campaign and earning Pro Bowl status.

“I felt like last year, I wasn’t there. Of course, we weren’t in the playoffs, but I still felt a great deal of grief just to have alienated my team because of a self-inflicted wound, basically,” Williams said. “I didn’t talk to anyone because I felt so embarrassed. I really didn’t. I kind of dealt with it on my own. . . . I really hate that feeling of not being on the field. It kind of scarred me in a good way.”

That’s why Williams played on Sunday. He believed that he needed to demonstrate more toughness and show his teammates they could rely on him.

“Trent has really become a pro football player. When he came in with so much talent so young, you could see some of the young ways, the young acts. But now, he’s really a leader,” Moss said. “He’s really that guy. He’s now at that [point] where he’s seen what he’s done and he realizes that there’s more than just lacing them up and playing football. It’s a job, and these people depend on you. I’m happy to be able to see him grow that way. Same with Fred.”