In their Week 1 win over the Kansas City Chiefs, the Buffalo Bills were able to contain Jamaal Charles and the Chiefs' rushing attack - aided by an early lead and a more physical defensive front. Heading into their Week 2 matchup with the Oakland Raiders, Gailey is expecting an even bigger challenge for his new-look run defense.

"Last week was a challenge in the run game; this will be a bigger challenge, in my opinion," Gailey told reporters on Wednesday. "They're so massive up front, and their backs are big, and strong, and downhill. Last week (in Kansas City), it was edge, hitting the crease, dip, dart; this is right at you, here we come, see if you can stop us."

In Week 1, Raiders running back Darren McFadden (22 carries, 150 yards) keyed a 190-yard rushing effort as Oakland beat Denver 23-20 on the road. Gailey knows that the Bills will need to do much better defending the run than Denver did to win, but also cautions that even if they do, they still won't have an answer as to whether the run defense is fixed from last year's last-place finish.

"We'll have a better idea. We won't have an answer; we'll have a better idea this week of where we are," Gailey said. "You don't get answers in Week 2."