Lawrence Tynes kicked a 31-yard field goal with 7:06 left in overtime to lift the New York Giants to a 20-17 victory over the host San Francisco 49ers in Sunday's NFC Championship Game.

The Giants capitalized on a second turnover by punt returner Kyle Williams, recovering the fumble at the 24-yard line to set up Tynes' winning kick and send them to their fifth Super Bowl appearance.

New York, which won its straight game and avenged a 27-20 regular-season loss to the 49ers in November, will face the New England Patriots in Super Bowl XLVI on Feb. 5 in Indianapolis.

It will be a rematch of Super Bowl XLII, when the Giants stunned the Patriots 17-14 and denied their hopes of a perfect 19-0 season. New York won at New England 24-20 earlier this season.

Williams, playing in place of an injured Ted Ginn Jr., not only fumbled the decisive punt with 9 1/2 minutes left in overtime but also had a bouncing punt nick his knee in the fourth quarter to set up New York's only touchdown of the second half.

Manning overcame six sacks to set playoff franchise records for completions and attempts, finishing 32 of 58 for 316 yards and a pair of touchdowns passes to Bear Pascoe and Mario Manningham. Victor Cruz had 10 receptions for 142 yards.

It was the fifth career road playoff victory for Manning, setting a league record, and gave New York a perfect 5-0 record in NFC Championship Games.

Niners quarterback Alex Smith was 12 of 26 for 196 yards and touchdown passes of 73 and 28 yards to tight end Vernon Davis, whose second score gave San Francisco a 14-10 lead with just over five minutes left in the third quarter.

The Giants went back ahead 17-14 with 8:34 to play in regulation, taking advantage of the first gaffe by Kyle Williams, who failed to get out of the way of a punt.

New York recovered at the 29-yard line and Manning needed only six plays to connect with Manningham on a 17-yard scoring strike to make it 17-14.

Williams partially atoned for the mistake by returning the ensuing kickoff 40 yards to set up David Akers' tying 25-yard field goal with 5:39 to play.

San Francisco (14-4) scored first when Smith connected with Davis on a 73-yard strike midway through the opening quarter. After that, though, the 49ers struggled to move the ball in the first half.

Conversely, the Giants had four drives of at least nine plays in the opening half and controlled the ball for 18 minutes.

Manning capped a 10-play drive with a 6-yard scoring pass to Pascoe with just over 11 minutes left in the second quarter and Tynes booted a 31-yard field goal with two seconds left for a 10-7 halftime lead.