New York Giants will face New England Patriots at Super Bowl XLVI after both teams secured dramatic wins in their respective championships.
A 31-yard field goal in overtime by Lawrence Tynes at a wet Candlestick Park earned a hard-fought 20-17 victory for the Giants, who made the playoffs after winning the regular season finale three weeks ago.
Tynes' crucial three points came after a decisive turnover in 49ers territory after San Franciso receiver Kyle Williams fumbled a punt in regular time.
For much of the rain-affected afternoon, the home side's defense appeared likely to withstand anything the Giants threw at them as visiting quarter-back Eli Manning struggled to find his groove early in the game.
The 49ers, on the other hand, applied early pressure which culminated in QB Alex Smith connecting with tight-end Vernon Davis for a 73-yard touchdown.
Having been kept at bay for the first quarter, the Giants responded early in the second when Manning hit full-back Bear Pascoe with a short pass for a touchdown to complete a 10-play 69-yard drive.
The 49ers gained the upper hand in the third quarter when Smith connected with Davis for a 28-yard touchdown for a 14-10 lead after San Franciso's defense cramped the Giants offense.
The score stayed the same going into the fourth quarter until Williams' fumble, which bounced on his knee following a Giants punt, led to a turnover.
New York took advantage when Manning, who had discovered his laser-like accuracy, found wide receiver Mario Manningham for a 17-yard touchdown after a six-play drive.
A 25-yard field goal by 49ers kicker David Akers squared the scoreline at 17-17 took the game into overtime and sudden death before Tynes kicked the NFC Championship winning points.
Meanwhile, the Patriots edged out the Baltimore Ravens 23-20 to reach their fifth Super Bowl in 11 years after Ravens kicker Billy Cundiff hooked a potential game-tying 32-yard field goal attempt wide in the final seconds of the game.
Tom Brady will lead the Patriots in his record-equalling fifth Super Bowl appearance but the New England quarter-back was not at his best at the Gillette Stadium on Sunday night.
He threw for 239-yards and completed 22 of 36 passes, but failed to deliver any touchdown passes and threw two interceptions.
After a cagey opening to the game, Patriots running back BenJarvus Green-Ellis rushed for 68 yards from 15 carries, which included a seven-yard touchdown to give New England a 13-10 lead at the intermission.
The Patriots increased their lead to 16-10 courtesy of a Stephen Gostkowski 24-yard field goal, but Baltimore earned their first lead of the game when Torrey Smith caught a quick Joe Flacco pass and rushed 29yards for a touchdown to take the score to 17-16.
A 39-yard field goal by Cundiff took Baltimore's lead to 20-16, but Brady responded with a one-yard scoring dive early in the fourth quarter to put the Patriots ahead for good.
''Just got to give all the credit to the players,'' Patriots coach Bill Belichick told the Gillette Stadium crowd during trophy ceremony on field.
''Those guys fought all year, just like today. It wasn't all perfect but they fought to the final gun and came out on top."
The Giants will be looking to emulate their 2008 Super Bowl success when they defeated the heavily favoured - and undefeated - Patriots to lift the Vince Lombardi trophy.
Super Bowl XLVI will be held in Indianapolis on 5 February.
