Not only do the Steelers have a chance to become the first team since 1991 to lead the NFL in total defense, rush defense and pass defense, they also are on pace for allowing the fewest yards per play since the 16-game schedule was instituted in 1978.

After 13 games, the Steelers allow an average of 3.88 yards per play, which would eclipse the mark set by the 1979 Tampa Bay Buccaneers (3.89) if they are able to maintain that level in the final four games

"That's incredible," said inside linebacker Larry Foote.

"It's very complicated," said inside linebacker James Farrior. "It's tough to just be dominating in one facet of the game. When you take one aspect away, it's hard. When you try to do both, it's double hard."

Even if the Steelers would finish with an average of 3.88 yards allowed per play, it still would not be a club record.

Three other Steelers defenses finished with a lower yards-per-play average: 1974 (3.56), 1973 (3.77) and 1976 (3.84), though each was in a 14-game schedule.

In addition to leading the league in total defense, rush defense and pass defense, the Steelers also have allowed the fewest points (170), fewest number of rushes of 20 yards or longer (2), fewest number of pass plays of 20 yards or longer (17) and fewest number of pass plays of 40 yards or longer (1).

"They just aren't allowing a whole lot of big plays, and, at this level, I don't think anybody really understands how difficult that is because every week you're playing against top athletes," said defensive coordinator Dick LeBeau. "That's why we are where we are."

Roethlisberger bounces back

Quarterback Ben Roethlisberger, who left Wednesday's practice early after appearing to twist his knee, went through a full practice yesterday without any difficulty.

"Ben is fine," coach Mike Tomlin said. "He was a full participant today."

Safety Troy Polamalu (calf) did not practice for the second day in a row but is expected to work today and play against the Dallas Cowboys.

McFadden or Gray?

Tomlin would not say if Bryant McFadden, who will return after missing six games with a broken right forearm, will replace William Gay as the starter at left cornerback.

"Hopefully we can play both of those guys," Tomlin said. "You've got to acknowledge that it's been six weeks since Bryant has played Football. But he has been practicing. We will continue to work that and see how it develops as the week goes on.

"Both guys have shown they are capable of playing and playing at a high level. That's a good problem to have. We will weigh those options a little later in the week."

'Super Bowl' for Latins

The Steelers and Cowboys aren't just vying for the title of America's Team; they might be competing to be Latin America's team, too.

Because of the popularity of the two teams, Sunday's game at Heinz Field will be the only one broadcast on site this season by Fox Sports Latin America, which typically broadcasts two games a week in Spanish from the studio.

The game, which will be broadcast to 16 Latin America countries, is so big that hundreds of Latin American fans will attend the game, including two Mexican senators.

"This is our Super Bowl," said Fernando Von Rossum Jr., who broadcasts the game with his father for Fox Sports Latin America.