NEW ORLEANS - It should have been a routine chip shot for Saints playoff hero Garrett Hartley, a 29-yard field goal in overtime to keep New Orleans unbeaten.

Somehow, the same kicker who set a Super Bowl record with three field goals longer than 40 yards hooked it wide left from the right hash mark. Minutes later, the defending champions' charmed run ended — and Falcons players stormed the Superdome field in celebration — when Matt Bryant drilled a 46-yard field goal with 1:55 left in the extra period to lift the Atlanta Falcons to a 27-24 victory Sunday.

"I missed basically an extra point," Hartley said. "It was clearly my mistake. ... It's the highs and lows of being a kicker."

Atlanta would have won in regulation if not for Hartley's tying 32-yard field goal with 4 seconds left in regulation.

The Falcons won the coin toss and received to start overtime, but the Saints held, setting the stage for reigning Super Bowl MVP Drew Brees to lead New Orleans to another dramatic win.

Brees drove the Saints to the Atlanta 11-yard line. Resigned to defeat as he watched from the sideline, Atlanta's Tony Gonzalez took off his receivers' gloves. Then Hartley hooked an ugly kick to the left for his third miss this season.

"I was absolutely stunned," Gonzalez said. "I thought for sure the game was over."

Even longtime public address announcer Jerry Romig had started into his typical "It's good!" refrain as officials began waving their arms sideways and cheers faded to groans in the Louisiana Superdome.

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Hartley's hook was eerily reminiscent of a miss on a potential gamewinner against Tampa Bay last season before the Buccaneers rallied for the win. It also resembled a pair of less consequential misses in New Orleans' season-opening win over Minnesota.

"I missed a big kick last year and was able to learn from it," Hartley said. "I plan on doing the same thing."

The game was a back-and-forth thriller that one would expect from longtime rivals who appear to be the best teams in the NFC South. There were four lead changes amid bizarre blunders and big plays.

Matt Ryan passed for 228 yards and touchdowns of 13 yards to Gonzalez and 22 yards to Roddy White to give the Falcons (2-1) their second straight win. Michael Turner added 30 carries for 114 yards and a 1-yard TD plunge.

Gonzalez wound up being Ryan's top target with eight catches for 110 yards, while White had five catches for 69 yards.

"This is a huge victory for us," Ryan said. "We have a lot of high expectations of ourselves and we fought the entire game to get us in position to win."

Lance Moore had a pair of TD catches for New Orleans (2-1), including a career-long 80-yarder. He finished with six catches for 149 yards and also had a career-long 72-yard punt return to set up Jeremy Shockey's short TD catch on New Orleans' first drive.