BALTIMORE — The Baltimore Ravens dug deep into their past to secure an easier path in the immediate future.

Using a stellar performance from the defense and an efficient effort from the offense, the Ravens beat the Buffalo Bills 19-7 Sunday to earn the No. 2 seed in the AFC and a first-round bye in the playoffs.

Baltimore needed San Diego to lose to Arizona in order to gain the top seed in the conference. The Chargers won, 27-20.

Chris McAlister returned an interception 31 yards for a touchdown and the Ravens yielded only 39 yards rushing to put a pretty bow on the finest regular season in franchise history. Baltimore (13-3) will enter the playoffs with a four-game winning streak and nine wins in its last 10 games.

Matt Stover kicked four field goals for Baltimore, which didn't score a touchdown on offense — and didn't need one. That's because the defense carried the day, just as it did in 2000 when the Ravens marched to their lone Super Bowl title.

Steve McNair, who has revived the Baltimore offense, went 23-for-35 for 216 yards in directing an attack that on Sunday was conservative yet effective.

McAlister's touchdown provided the Ravens with a 16-7 lead with 3:46 left in the third quarter. The Pro Bowl cornerback stepped in front of Peerless Price, reached high to grab the pass from J.P. Losman and scurried down the left sideline, holding the ball aloft in his right hand over the final 15 yards.

It was McAlister's career-high sixth interception of the season, and the fifth time this season the Ravens returned an interception for a touchdown.

Baltimore expanded its lead to 19-7, and Samari Rolle picked off Losman's pass in the end zone with just over two minutes left to seal the win.

Losman went 20-for-35 for 237 yards, but Buffalo (7-9) fell short in its bid to finish .500 in its first season under coach Dick Jauron.

Baltimore locked up a playoff berth two weeks earlier, but the Ravens coveted the first-round bye. It will open the playoffs at home on Jan. 13 or 14.