LANDOVER, Md. — Ben Roethlisberger exchanged high-fives with teammates after the touchdown that extended the Pittsburgh Steelers' lead in the fourth quarter.

With his left hand. While wearing a baseball cap.

With Roethlisberger sidelined after reinjuring his throwing shoulder, the local kid who used to sneak into Washington Redskins games made an unexpected appearance on the field.

D.C. native Byron Leftwich came on at halftime and led two touchdown drives in the Steelers' 23-6 victory over the Redskins last night.

"We all know Ben's the guy," Leftwich said. "Ben's the quarterback of this football team, and I know I was going to be there in case something happened. Something happened today."

What happened was Roethlisberger's 1-yard sneak that gave the Steelers a 10-6 lead in the final minute of the first half. On the play, the quarterback reaggravated the slightly separated right shoulder that has bothered him since the second week of the season.

"I have no update on Ben at this point," coach Mike Tomlin said. "Potentially, he was capable of going back in the game, but we went down the field with Leftwich in there to start the second half. We'll just see how he is."

Roethlisberger was 5 of 17 for 50 yards and an interception, while Leftwich went 7 of 10 for 129 yards and a touchdown for Pittsburgh (6-2).

The Steelers' top-rated defense had seven sacks and became the first team this season to intercept Jason Campbell.

Leftwich's big play was a 50-yard completion to Nate Washington, which set up a 1-yard TD run by Willie Parker with 10:22 left in the third quarter.

Early in the fourth quarter, Leftwich had a 5-yard scoring pass to Santonio Holmes to make it 23-6.

Campbell was 24 of 43 for 206 yards and two interceptions for Washington (6-3).