Argentina's Angel Cabrera tonight added a Masters green jacket to his 2007 US Open victory - and stopped 48-year-old American Kenny Perry becoming the oldest major champion in history.
The pair had tied with Perry's Ryder Cup team-mate Chad Campbell on 12 under par after a day earlier dominated by magnificent charges and bad finishes from Phil Mickelson and Tiger Woods.
Campbell went out when he missed a par putt of under four feet on the first hole of the sudden-death play-off.
Cabrera made a seven-footer to stay alive there and triumphed when Perry, who had bogeyed the final two holes when two ahead, missed the green at the second extra hole and failed to get up and down.
At 69th in the world Cabrera became the lowest-rated Masters champion since the rankings began in 1986 - and his triumph came 41 years after his compatriot Roberto de Vicenzo became one of the unluckiest losers ever in major golf.
De Vicenzo was all set to go into a play-off with American Bob Goalby at the same Augusta National course, but signed for a par four on the 17th when he had actually taken three.
The rules stated that he had to accept the higher score and so he is forever listed as a Masters runner-up.
That looked likely to be Cabrera's final position as well, but Perry brought back horrible memories of his finish to the 1996 US PGA championship.
On that occasion he was two ahead with one to play, but carded a closing bogey six, sat in a television studio and watched Mark Brooks birdie, then lost the play-off.
Cabrera, 39, had teed off with the chance to become the first Masters champion to have four rounds in the 60s. But as it turned out a one-under 71 was good enough.
Japan's Shingo Katayama finished fourth, Mickelson fifth and Woods joint sixth with fellow Americans Steve Flesch, Steve Stricker and little-known John Merrick.
In their worst collective showing since 2000, no European finished in the top 16. Ulsterman Graeme McDowell was best, four under and joint 17th after a 69.
Woods and Mickelson had earlier served up what for most of the round was one of the great head-to-head duels ever in majors.
They both came from seven back to be only one behind with two to play, but could not eliminate the mistakes which would have put more pressure on the leaders over the closing stretch.
Woods bogeyed the last two like Perry, but it was of no comfort to Mickelson that he beat his deadly rival by one. He made the bigger blunders at the crucial moments.
The 2004 and 2006 champion, out in a dazzling record-equalling 30 that brought electricity to the atmosphere around the entire course, first messed up the short 12th by going in the water and taking a double bogey five.
When he two-putted the long 13th he re-ignited his chances and at the 15th he drilled a majestic iron to four feet. If the eagle putt had gone in he would have joined Perry out in front, but he missed.
Woods had also birdied the 13th and after missing a 20-foot eagle putt two holes later hit his tee shot to the 170-yard 16th to four feet and drew level with Mickelson.
They were both one behind, but Woods blocked himself out off the 17th tee, could not find the green and bogeyed.
Mickelson, meanwhile, hit his approach to six feet, but missed that as well and then, while Woods was in more tree trouble on the last, found the cavernous fairway bunker and, unlike Sandy Lyle so famously in 1988, came up short of the green and could not save par.
Perry, joint overnight leader with Cabrera, parred the first 11 holes, then made a 30-footer from the fringe of the short 12th.
Three-putting the next for only a par heightened the tension, but after being joined on 12 under by Campbell's birdie at the 15th he did the same to get his nose back in front - and then almost holed-in-one at the short 16th.
The tap-in birdie looked as if it might be the shot that won it, but it was not to be.
He went long at the 17th, chipped off the front of the green and failed to get up and down.
At the last he found the fairway bunker, but still had a 15-foot chance to eclipse Julius Boros - US PGA champion in 1968 - as golf's oldest major champion.
He could not make it, though, and was made to pay the price.
Ian Poulter and Lee Westwood were joint 10th with Woods and Mickelson when they resumed, but the former shot 74 for two under and Westwood, having double-bogeyed the seventh, dropped a shocking seven shots in the last four holes for a 79 - the worst round of the day.
As for Open and US PGA champion Padraig Harrington, he lost a ball up a tree and added a seven on the ninth to his nine on the second on Saturday.
Having started with a 69 to keep the "Paddy Slam" dream alive he closed with three successive 73s for level par.
Nineteen-year-old Rory McIlroy completed a memorable debut - for all sorts of reasons - with birdies at six of his last 10 holes for a 70 and two under aggregate.
On the same mark were last week's Houston Open winner Paul Casey, Poulter, Justin Rose and, in a performance few would have expected, 51-year-old Sandy Lyle, the 1988 champion.
Rose eagled the 13th and 15th and in his second round Lyle had five successive birdies.
But in the end the 2009 Masters will be mostly remembered for errors - by Mickelson, Woods and Perry in regulation play and then by Campbell and Perry in the play-off.
Cabrera went in the trees when the three-man shoot-out began and although his second shot hit a tree and finished way short of the green, he salvaged par and minutes later was being helped into his jacket by last year's winner Trevor Immelman.