Ben Shpigel

FOXBOROUGH, Mass.: For some franchises, four years is a shard of time. For the New England Patriots, it is a millennium. Their aura of invincibility had faded with two playoff losses at Gillette Stadium, but that was then. That was before the Patriots upheld their top-seeded status in the AFC and roared back to the Super Bowl.

They outlasted the Baltimore Ravens on Sunday, 23-20, erupting when Billy Cundiff hooked a 32-yard field-goal attempt wide left with 12 seconds remaining. As their sideline spilled onto the field, the Ravens stood on theirs in disbelief.

New England captured its first AFC title since the 2007 season on the strength of its defense, which in the fourth quarter stunted two Baltimore drives, and will play the winner of the NFC championship — the Giants — on Feb. 5 in Indianapolis. It will be the Patriots’ fifth Super Bowl appearance in 11 years, and their fifth under Bill Belichick and Tom Brady, who tied his idol, Joe Montana, for most postseason victories with 16.

With Indianapolis down and Pittsburgh out, the Ravens and the Patriots climbed to the top of the AFC. Baltimore did so with its defense, which held Brady without a touchdown pass but could not keep him out of the end zone, yielding his 1-yard touchdown run — on fourth down — with 11 minutes 29 seconds remaining for the game’s final points.

Twice the Patriots stunted Baltimore drives in the fourth quarter, once on an interception by Brandon Spikes, then by forcing an incompletion on fourth down.

But in the final minutes, New England’s defense nearly broke. Taking over at their 21 with 1:44 remaining, the Ravens marched to the New England 14, aided by two third-down completions. On first down, Lee Evans dropped a pass in the end zone. Baltimore did not gain another yard. Or score another point.

The Ravens’ loss overshadowed an excellent game by Joe Flacco, who completed 22 of 36 passes for 306 yards and two touchdowns and an interception. He engineered a brilliant 11-play, 78-yard drive in the third quarter that culminated in a 29-yard touchdown catch by Torrey Smith, who broke a tackle by Sterling Moore at the 25 and sprinted down the sideline.

But the Ravens could only produce a field goal after recovering a fumble on the ensuing kickoff.

With New England trailing, 20-16, late in the third quarter, Brady did what he had done so many times before, particularly in the Patriots’ friendly confines. He capped a 59-yard drive with a dive over his linemen on fourth-and-goal from the Baltimore 1, putting New England ahead to stay.

Quarterback disparity

At halftime, perhaps the most surprising element involved not the score — Patriots 13, Ravens 10 — but the disparity between the quarterbacks. Flacco had completed a higher percentage of his passes (68.8 to 58.3), thrown for more yards (162 to 146), amassed a better rating (122.4 to 58.7) and committed fewer turnovers (none to one).

The ferocity of the Ravens’ defense did not startle Brady, whose 55.9 completion percentage in five previous games was his lowest against one team.

But Baltimore moved him around the pocket and held firm in the red zone, allowing three field goals. After shredding the Denver Broncos for six touchdowns in the divisional round, Brady did not throw for one Sunday.

The Patriots dismantled opponents during their nine-game winning streak, prevailing by an average of 18.7 points, but one question persisted: Was their dominance a function of outstanding play, or merely the inferiority of their opposition? Until New England did so this season, no team in the Super Bowl era had reached its conference championship without beating a team with a winning record, according to the Elias Sports Bureau.

In one sense, then, the Ravens were the ultimate test for New England: They won all seven games against playoff-bound teams. Last week the Patriots said they would not draw on their wild-card defeat to Baltimore two years ago as motivation — neither would the Ravens — but it was difficult to imagine their not remembering how Ray Rice torched them that day, leading a 234-yard rushing effort, and vowing not to let him beat them again.

A Baltimore offense that sputtered last week against the Houston Texans resembled game-day traffic to Gillette Stadium. It was slow. It stalled. And it moved backward, yielding two sacks while netting negative-6 yards on its first three possessions.

Its great leap forward came late in the first quarter, after Lardarius Webb intercepted Brady, on a 42-yard pass to Smith off a nifty bootleg that fooled the Patriots’ secondary. Had Flacco not underthrown the pass, forcing Smith to dive, Smith could have crabwalked the remaining 28 yards into the end zone.

But the Ravens, who failed to score a touchdown over the final 46:08 against Houston, extended that streak of futility and had to settle for Cundiff’s first field goal.

Flacco outclasses

Baltimore finally produced a touchdown midway through the second quarter, with a 6-yard pass from Flacco to Dennis Pitta that evened the score at 10-10. That touchdown also punctuated a revival for Flacco, who during that drive had thrown with increased accuracy, touch and conviction.

Such precision must have looked different to the Patriots. Among the quarterbacks toppled by New England in nine games since Eli Manning won here on Nov. 6: Tyler Palko, Dan Orlovsky and Rex Grossman. Add in Ryan Fitzpatrick and Matt Moore. Flacco outclassed them all.

The Patriots, whose defense ranked 31st in the regular season, wanted to lure the Ravens into a high-scoring game, confident that Brady and his array of options would overcome.

They overcame, just not the way they would have figured.