ATLANTA -- Kyle Williams is the Buffalo Bills' longest-tenured player. Over his 11 seasons, he has watched the New England Patriots win the AFC East 10 times and beat the Bills in 19 of the teams' 22 contests.

This season, the Patriots look vulnerable. Preseason discussion about another 16-0 season has fizzled into a leaky defense that entered Week 4 allowing a league-worst 31.7 points per game and let the Carolina Panthers score 33 points in another loss Sunday, dropping New England to 2-2.

For some Bills fans, the Patriots' slipping is an opportunity to soak in a change atop the AFC East. The Bill sit atop the division at 3-1. But when approached in the locker room Sunday after Buffalo's 23-17 upset win over the Atlanta Falcons, Williams took a different view on the topic.

"That doesn't have anything to do with me, and I don't care," he said of the Patriots' issues and the division picture.

Jerry Hughes celebrates after the Bills' upset win at Atlanta gave first-place Buffalo a 3-1 record. Kevin C. Cox/Getty Images

Williams is right. At the moment, the Bills do not have to worry about the Patriots. Used to perpetually chasing the Patriots by October, Buffalo is instead in the driver's seat in the division. The Patriots, the emperors of the AFC East in all but two seasons since 2001, are not on Buffalo's schedule until a pair of meetings in December.

New England might not be on the minds of most in the Bills' locker room, but that does not mean Buffalo does not respect the potential challenge posed by the Patriots should they solve their defensive struggles. The Bills could also have issues pop up.

Both center Eric Wood and Williams were part of a Bills squad in 2011 that rode Ryan Fitzpatrick's arm to a 5-2 start, including an uplifting home win over the Patriots, only to collapse to a 6-10 finish. The Patriots went 13-3 and were a failed last-minute drive away from winning Super Bowl XLVI.

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"I've had this feeling that I don't want to jump the gun," Wood said in the locker room Sunday. "I still think [the Patriots] will win a whole bunch of games this year. For us to win the division, we'll need to win a lot of them, too. I'm very leery ever looking past just the next game, and we've got a big one this week at Cincinnati."

The Bills have benefited from good health so far this season. They have only two players on injured reserve, both were injured in training camp and not expected to make the 53-man roster. Left tackle Cordy Glenn has missed two games, defensive tackle Marcell Dareus missed Week 3 and defensive end Shaq Lawson missed Sunday's game. Otherwise, the Bills' starting group has stayed intact.

As with any team at this stage of the season, there is room for improvement in several areas. The Bills' run defense allowed the Falcons to average 5.1 yards per carry after the Broncos averaged 4.8 yards per rush in Week 3. Their offense has, at times, been unable to overcome defenses stacking the box and bottling up LeSean McCoy, who ran 20 times for 76 yards on Sunday. The Bills have stumbled on 10 three-and-out drives the past two games, including six that gained zero or negative yards.

But when the Bills' offense has failed to move the ball, the defense has been there to pick up the slack. Because of that, the Bills sit in first place in the AFC East.

"Yeah, it feels good," Bills coach Sean McDermott said Sunday. "The guys work hard. Still a long way to go."