FOXBORO — With wayward pieces of red, blue and silver confetti dotting the locker-room floor behind him, New England Patriots linebacker Tedy Bruschi, his arms bright red with the wounds of the day, let out a satisfied sigh.

 And to no one in particular, he said happily, “The Super Bowl!”

 Behind the stout play of Bruschi and his defensive teammates, the Patriots kept their undefeated season going for one last game, besting the San Diego Chargers, 21-12, in the AFC championship game on Sunday.

 The afternoon will be remembered for Laurence Maroney’s great second-half running, Kevin Faulk’s diving third-down catch, Tom Brady’s less-than-stellar play and Philip Rivers' gutsy performance on two ailing knees.

 But it was won by the Patriots' defense, doubted by some, yet undeniably able to rise to the occasion.

 New England held the Chargers' offense to four field goals, three of which came inside the red zone, where they had encountered some up-and-down results this season.

 "All year we were either giving up touchdowns or we were playing great," Mike Vrabel said. "There was no in between. I think you saw the great tonight."

 The Chargers, who had surprised the defending-champion Colts in Indianapolis last week to gain their first conference title game since 1994, got their first red-area trip after Brady's first of three interceptions Sunday.

 Quentin Jammer's pick put San Diego at the New England 40, and the Chargers were at the 20 after a five-yard Michael Turner run and a 15-yard facemask penalty on Vince Wilfork.

The Bolts advanced to the 8-yard line with an 11-yard pass to Chris Chambers and a one-yard pickup by Turner, but incompletions to fullback Lorenzo Neal and Chambers in the back of the end zone led them to settle for a 26-yard field goal from Nate Kaeding.

 The Patriots answered the Chargers' three points with seven; behind matching 14-yard gains by Randy Moss (on a reverse) and Faulk (screen), they drove to the 1-yard line. Maroney finished off the possession with his sixth touchdown in the last five games.

 Maroney finished the game with 122 yards on 25 carries (4.9 yards per), with 106 of those yards coming in the second half.

 New England’s defense again put up a wall at the goal line on the Chargers' next possession.

 On third and one from the Pats’ 30 and one receiver on the field, Rivers hooked up with Vincent Jackson for a 21-yard gain. But a pass for Antonio Gates at the goal line was broken up by Bruschi, and a dumpoff to Chambers on third and eight gained just three yards.

 And led to another 26-yard three-pointer by Kaeding, who entered the game 1 for 3 on postseason field goals this year.

 But the biggest goal-line stop came from revered veteran Junior Seau, whose desire to punctuate his Hall of Fame career with his first Super Bowl title has become the quest of this team.

 On San Diego's opening possession of the second half, when it again started with favorable field position thanks to another interception, the Chargers faced third and one at the 4.

 No sooner did Michael Turner get the ball than he was he met by Seau, who dropped him for a two-yard loss. Chargers coach Norv Turner elected not to go for it on fourth down.

 “It was a combination of a lot of things,” Seau said about his stop. “The D-linemen did a great job of taking up two guys. The call that was made was basically a call that I could shoot the gap. I don’t know if [defensive coordinator Dean Pees] called it because he knew I was going to shoot it anyway, or he called it because he felt something, but it was a great call.”

 After allowing Jacksonville to score touchdowns on two of three red-zone possessions last week, the Patriots tightened things up this week by getting back to basics.

 "We just kept playing; we stayed focused," Ellis Hobbs said. “Bill [Belichick] stressed all week: Do your job. If you do your job, everyone else will do their job.”

 "It's about guys not stepping outside their job and making plays, and trusting in your fellow teammates," Rodney Harrison said.

"We’ll watch film, and you’ll have five guys doing their jobs and one guy doing his own thing. You can't have that when you have the type of defense that we play, where everything is assignment-oriented.

 "You really have to make sure you're doing your assignment and not doing someone else's job. Junior made a great play down there, other guys made great plays, and with a great offense like that, if you can hold them to three points, that's a victory, and that’s what we did."

 By holding the Chargers to a quartet of field goals, the Patriots are now holding tickets to Super Bowl XLII, in which they’ll take on the New York Giants.