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The Buffalo Bills have played three road games this season against teams that are currently at or above .500. After beating the Pittsburgh Steelers in prime time at Heinz Field on Sunday night, they're 3-0 in those games.

In those three wins over the Steelers, Tennessee Titans and Dallas Cowboys, Buffalo has surrendered just 10.7 points per game.

That latest victory—a 17-10 triumph on Sunday Night Football—ensured that the Bills will head to the playoffs for the second time in three years. And while it remains extremely unlikely that they leapfrog the AFC East-leading New England Patriots, the win over Pittsburgh confirmed that pesky Buffalo will be a tough out in January, regardless of whether Sean McDermott's squad is in Orchard Park or elsewhere.

It, of course, starts with that defense, which recorded two takeaways on short rest in Dallas and then turned Pittsburgh over on five occasions Sunday evening. That opportunism is something the Buffalo D lacked for much of October and November. The Bills had eight takeaways in September and just five in the next seven games, but now they're making splash plays against high-quality opponents.

Three of those splash plays came with the game on the line in a hostile environment Sunday. In the second half of a critical, closely contested home game, Pittsburgh's final six series resulted in three three-and-outs and three interceptions.

"They've got a really good defense," Steelers head coach Mike Tomlin told reporters after the game. "We knew that, and they confirmed it."

The Bills are always in games because they rarely bomb defensively. They've surrendered more than 21 points just twice all season, and it's become clear that the 31 they gave up to the Philadelphia Eagles was a tremendous aberration. Only the Bills and Seattle Seahawks have held Lamar Jackson and the Baltimore Ravens offense to fewer than 20 first downs this season, and only the Bills, Patriots and New Orleans Saints have held the Cowboys' highly rated offense to fewer than 20 points.

The Philly game is their only loss this season by more than one score, which is a testament to the idea that they're greater than the sum of their parts. Tre'Davious White is one of the league's best cornerbacks, defensive end Shaq Lawson is finally emerging, and there's a lot of hope for youngsters Tremaine Edmunds and Ed Oliver, but the Bills lack defensive superstars and that's OK.

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What they do have is what I'd call extreme depth, with that aforementioned foursome well-supported by veterans Jerry Hughes, Trent Murphy, Jordan Phillips and Star Lotulelei up front, Matt Milano and Lorenzo Alexander at linebacker and Kevin Johnson, Micah Hyde and Jordan Poyer in the secondary.

When you have that many quality parts, several can afford to have off days without costing the team dearly.

Put it all together, and the Bills should scare the hell out of the Patriots, who were lucky to beat Buffalo 16-10 in a game in which the Bills lost quarterback Josh Allen to a head injury in the fourth quarter and gave up a special teams touchdown back in September.

They should terrify the Ravens, who had won five of their previous six games by 14-plus points before having to grind out a victory in Buffalo last week. A rematch could work to the Bills' advantage, mainly because that defense now has firsthand experience defending Jackson.

The AFC West-winning Kansas City Chiefs had a minus-12 scoring margin at home before recently beating up on the Oakland Raiders and Denver Broncos at Arrowhead, and they've lost at home to the Indianapolis Colts, Houston Texans and Green Bay Packers. Buffalo appears to be a taller hurdle than all three of those foes, so it's safe to assume the Chiefs want nothing to do with a tough team like the Bills on Wild Card Weekend.

Buffalo could end up drawing the Titans on the road that weekend, which would be daunting for a Tennessee team that was completely smothered by the Bills defense in a 14-7 home loss to Buffalo in October. But the AFC South is more likely to go to the Texans, who just a week ago were embarrassed by the lowly Broncos at home.

Nobody in the AFC is infallible, home or away. Even New England's 21-game Foxborough winning streak is now over.

This might be the perfect year for a wild-card team like the Bills to make a run, and the stars appear to be aligning.

Now, an inconsistent offense that rarely lights up the scoreboard could easily sink the Bills. For the franchise to play spoiler and win its first postseason game this century, it'll need at least a steady performance from Allen and Co. That unit has been held to 20 or fewer points in three of Buffalo's last four games, but the schedule has been tough, and by no means have the Bills been totally shut down on that side of the ball.

Sunday's game was their first multi-turnover affair since September, and in their defense the Steelers are the most takeaway-happy team in football. The Bills scored 10 fourth-quarter points to come back on the road and get the best of one of the hottest and most defensively stout teams in the league, and that might not have happened if not for a game-changing 40-yard completion from Allen to John Brown on the first play of the game-winning drive.

Allen attempted just three deep passes. He hit his receiver in the hands on all three, completing two. The other resulted in an interception off a deflection. His final numbers (13-of-25, 139 yards, one touchdown and one pick) weren't sexy, but it was actually a performance that contained some promise considering the circumstances, including the fact that he was trying to bounce back from a poor showing against Baltimore. Plus, he also rushed for 28 yards and scored his ninth rushing touchdown of the season.

Allen and the offense usually run well and rarely turn the ball over. Throw in a big throw from time to time, and that's often all you need when your defense is as talented and productive as Buffalo's.

The rest of the AFC is officially on notice now. The Bills are going to the playoffs, and that oughta be a frightening thought for the rest of the conference's Super Bowl contenders.

Brad Gagnon has covered the NFL for Bleacher Report since 2012.