The Buffalo Bills' porous rush defense won't see Ronnie Brown lining up in the Miami Dolphins' backfield in their second meeting this season, but their assignment Sunday isn't likelier to be any easier.

Ricky Williams' back-to-back 100-yard games have given Miami a lift after Brown's season-ending injury, and he'll look to keep the Dolphins' highly-ranked ground attack moving and boost their playoff hopes at Ralph Wilson Stadium against the sputtering Bills.

Miami (5-5) looked to be in deep trouble in its attempt to defend its AFC East title after losing three straight games to begin the season, but it's won five of seven since to become a factor in the wild-card picture while giving itself a chance to remain in the division race.

The Dolphins' turnaround began against Buffalo (3-7) in Week 4, as their run-heavy offense gashed the Bills for a season-high 250 yards in a 38-10 victory.

Brown had 115 yards and two touchdowns while Williams totaled 85 yards and a score, but only Williams will be in the backfield Sunday as Miami seeks its fourth straight win over Buffalo. Brown suffered a season-ending foot injury in the Dolphins' 25-23 win over Tampa Bay on Nov. 15, leaving Miami without its wildcat triggerman and putting the onus on Williams to keep the team's fourth-ranked rushing attack (156.0 yards per game) going.

Williams ran for 102 yards in the win over the Buccaneers, and kept the offense moving Nov. 19 at Carolina. He gained 119 yards on the ground and scored three touchdowns - two rushing - in the Dolphins' 24-17 win, making the 32-year-old the oldest Miami running back to run for 100 yards in consecutive games.

"He's not 32, I don't care what he says," rookie receiver Brian Hartline said. "He definitely doesn't look 32 out there, and he definitely has a lot of gas left in his wheels."

Williams - the AFC's offensive player of the week - hasn't rushed for 100 yards in three straight games since 2003.

After the win over the Panthers put Miami at .500 for the first time this season, the Dolphins' biggest task may be avoiding a letdown in Buffalo with a visit from division-leading New England looming next week.

"It puts us on the right track," Williams said. "We have been trying to get here all year, and we finally got here. It's just the next step to where we want to go."

The Dolphins' big rushing effort against the Bills in Week 4 was part of a four-game stretch in which Buffalo allowed 240.5 yards per game - including an NFL season-high 318 in a 16-13 win over the New York Jets on Oct. 10.

The Bills' struggles on both side of the ball were enough to get coach Dick Jauron fired after a 41-17 loss at Tennessee on Nov. 15, and while they played better last Sunday in Jacksonville, the result was the same. Mike Sims-Walker caught a touchdown from David Garrard with 56 second left to lift the Jaguars to an 18-15 win in Perry Fewell's debut as interim coach.

"Emotional week for all of us and this was an emotional loss for us," Fewell said. "I thought our guys fought their hind ends off. They battled down to the wire. We just didn't get it done."

Fewell's home debut will come days after the team met with former Denver coach Mike Shanahan about its vacancy, but while the team's temporary leader may only be on the sidelines for six games, there were some positive developments in Fewell's debut.

Buffalo held Maurice Jones-Drew to 66 rushing yards and Jacksonville as a team to 102, the best it's done against the run since holding Tampa Bay to 57 yards in a Week 2 win. Additionally, Terrell Owens caught nine passes for 197 yards and hauled in his first touchdown since scoring against the Bucs.

Ryan Fitzpatrick threw two interceptions in Jacksonville, but his connection with Owens - which included a 98-yard pass in the third quarter - has the quarterback optimistic about the Bills' offense.

"It's been a long and frustrating season, and it hasn't gone the way we want offensively," Fitzpatrick said. "But we've got six games now to kind of turn that around and make a positive out of it."

Some key injuries, however, may make connecting with Owens tougher this week. While running back Marshawn Lynch is expected to play after leaving Sunday's game with a shoulder injury, Buffalo lost guards Eric Wood (broken leg) and Seth McKinney (knee) for the season, leaving it with five healthy offensive linemen on the roster.

The Bills have allowed 109 fourth-quarter points this season, second-most in the NFL behind Miami's 110.