CHICAGO - Jason Peters, the offseason upgrade at left tackle, returned after a week off dealing with his ankle injury.

He was leaned on heavily in the Eagles' first drive, which earned them a field goal, and he played flawlessly on that drive, which set the tone for him during the Eagles' first two possessions. The first brought a field goal, the second a touchdown.

Then came the third possession, and the play on which he aggravated the ankle injury.

He didn't come out. But his play got worse.

Trying to get a jump on defensive end Alex Brown, Peters was hit with a false-start penalty early in the second quarter, and was largely responsible for the Bears' first sack.

Then, late in the third quarter, he dived and whiffed on a block of Brown . . . and tripped Brown as Brown raced past. That 10-yard penalty short-circuited an Eagles drive.

"I rolled it," Peters said. "I just kept going. I tried not to think about it."

So, all things considered, Peters' night wasn't as bad as it seemed.

"Brown was getting off the rock," he said of Brown's quickness. "I was late off the ball. But man, when I'm healthy, nobody can beat me."

He played through pain 2 weeks ago, too, but was sidelined the week after. Don't expect him to sit again, especially with the Eagles 6-4 and in the postseason chase.

"Whatever it takes, man," said Peters, who played on five poor Bills teams before this season. "I've never been to the playoffs. I'll do whatever it takes."