Buffalo Bills defensive end Chris Kelsay doesn't require a crystal ball to guess what the Houston Texans will have in store for them this weekend.

How's a heavy dose of running back Arian Foster sound?

"That's evident," Kelsay said Wednesday. "There's no doubt in my mind that they're going to come out and try to establish the run."

The Bills near season-long struggles in stopping the run are well documented. They've allowed an NFL-worst 1,238 yards rushing, and are coming off a game in which Chris Johnson had a season-best 195 yards in Tennessee's 35-34 win two weeks ago.

Kelsay is still upset over how Johnson all but dared the Bills to stop him in the days leading up to the game. So he can only imagine what Foster might be thinking.

"Running backs look at playing us as an opportunity," Kelsay said. "It's our job as a defense to nip that in the bud right now. And that's our focus."

The Bills (3-4) had a bye week off to rest and regroup on defense. And their first test coming out of the break won't be easy in traveling to play at Houston (6-1) on Sunday to face a balanced offense that relies on Foster's imposing presence in the backfield.

"I'm very confident in what we can do," linebacker Nick Barnett said. "If we go down there and play with focus and determination and the will that we should, I think we should be able to stop him the way nobody's stopped him this year."

Pausing to gather his thoughts, Barnett then added: "So, we've just got to do it, though."

Easier said than done.

Since limiting Browns rookie Trent Richardson to 27 yards rushing in a 24-14 win at Cleveland on Sept. 23, Buffalo has given up a combined 937 yards rushing in its past four games.

Defensive tackle Kyle Williams has been around long enough to know opponents will continue to test the Bills' run defense.

"Whatever you seem to be having trouble with as a team, you always seem to find it," Williams said. "You're going to always seem to find it until you can stop it and prove they need to move on and try to do something else against you."

The Texans are also coming off a bye week, and coach Gary Kubiak was guarded when asked if he intended to take advantage of the Bills' inability to stop the run.

"We don't approach things that way," Kubiak said. "I don't know what it's going to take for us to be successful this weekend. You never know how a game's going to go. But we pride ourselves on being able to run the ball."

Foster hasn't slowed since 2010. Over the past 36 games, he leads the NFL with 3,499 yards rushing, 4,797 yards from scrimmage and 40 touchdowns. He's particularly been at his best at home, where he's averaging 109 yards rushing, 4.7 yards per carry and scored 23 times in 19 career games at Reliant Stadium.

This season, Foster's fifth in the NFL with 659 yards rushing and leads the league with 10 touchdowns (including one receiving).

He's a threat even when he doesn't touch the ball. The Texans take advantage of defense's keying on Foster by switching things up with an array of play-action passes.

"Yeah, everybody knows what's coming," Bills coach Chan Gailey said. "You know that the run game's coming. You know the play-action pass is coming. You know what you've got to stop. They're not fancy. They just do what they do extremely well."

The Bills insist their struggles against the run are easily correctible. They say the problems have emerged only when defensive players over-play their roles and fail to fill their run gaps.

"We have to play fundamental football, play square and don't let the offensive line take the defensive line out of the game," defensive tackle Marcell Dareus said. "I'm very confident in us getting it done from the beginning to the end. It's just putting it all together."

NOTES: Gailey all but ruled out DE Mark Anderson from playing Sunday. The starter has already missed two games with a knee injury. ... CB Terrence McGee returned to practice on a limited basis after aggravating a left knee injury against Tennessee. ... The Bills are only 986 yards rushing short of what they allowed last season.


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