INDIANAPOLIS - Peyton Manning was too busy trying to beat the San Diego Chargers to celebrate his record-breaking touchdown pass.

The Indianapolis star broke Dan Marino's single-season record with 56 seconds left in regulation, hitting Brandon Stokley on a 21-yard post pattern, but he still had a lot of work to do in the Colts' 34-31 overtime victory Sunday.

Edgerrin James ran for the tying 2-point conversion on a play Manning called at the line, and the Colts won on Mike Vanderjagt's 30-yard field goal on the first possession of overtime.

It was only then that Manning, finally, let go by pumping his fist in the air, giving high-fives to teammates and hugging six-time Pro Bowl receiver Marvin Harrison.

"At the time I threw it, there wasn't a lot of emotion for me, because if we don't get the 2-point conversion, this is a down locker room right now," Manning said. "The fact that it happened, we won the game. ... it sure made for an exciting day."

For three weeks, Manning downplayed the significance of Marino's record, football's equivalent of baseball's home-run mark, saying all he wanted to do was win.

In the closing minutes Sunday, Manning delivered.

Indianapolis (12-3) scored on its final two possessions to win its eighth straight and wrap up the No. 3 seed in the AFC playoffs.

"The way it happened on that drive, I think Johnny Unitas would have been proud," Manning said.

The AFC West champion Chargers (11-4) tried to prevent the high-scoring Colts from torching their poor pass defense. They blitzed, used extra defensive backs and changed their looks to confuse Manning.

It worked effectively for three quarters.

Manning, who had been sacked just nine times in the first 14 games, went down four times against the Chargers. He fumbled twice, threw an interception and appeared to be pressing as he overthrew receivers, mistimed throws and ran out of trouble.

Then he reverted to his usual form, finishing 27-of-44 for 383 yards and the TDs. He has 49 touchdown passes this season, one more than Marino had in 1984, and remained on pace to shatter Steve Young's NFL record for passer rating next week in Denver. Manning is at 121.4, Young finished at 112.8 in 1994.

"We wanted to confuse him a little bit," linebacker Donnie Edwards said. "But when we had to make plays, we came up short."

The Colts (12-3), winners of eight straight, wrapped up the No. 3 seed in the AFC. Visiting San Diego had its eight-game winning streak broken, but also will host a first-round playoff game.

The Pittsburgh Steelers (14-1) are the top seed in the AFC after a 20-7 victory over Baltimore, and the New England Patriots (13-2) also will have a first-round bye after beating the New York Jets 23-7.

The Jets (10-5), still a win away from securing a AFC wild-card spot, will finish the season with a road game against the St. Louis Rams. Denver (9-6), which beat Tennessee Saturday night, is in control of the other AFC wild-card spot.

Buffalo (9-6) is still firmly in the mix after a 41-7 win over San Francisco. The Bills need just a win and a loss by either the Broncos of the Jets to be a wild-card team. Baltimore and Jacksonville, a 21-0 loser to Houston, also are mathematically alive for playoff spots.

In the NFC, Seattle (8-7) clinched a playoff spot with a 24-21 win over Arizona, and could wrap up the NFC West with a loss by St. Louis on Monday night. The Cardinals were eliminated.

The Carolina Panthers (7-8) beat Tampa Bay 37-20 to move a win away from a wild-card spot after a 1-7 start. The New Orleans Saints (7-8) also stayed in the race with a 26-13 victory over Michael Vick-less Atlanta. The Saints and Panthers play each other to finish the season.

In Sunday's games other games, it was: Detroit 19, Chicago 13; Cincinnati 23, the New York Giants 22; Dallas 13, Washington 10; and Miami 10, Cleveland 7. On Saturday, Kansas City beat Oakland 31-30, and Denver topped Tennessee 37-16. On Friday, Green Bay beat Minnesota 34-31.