American Bubba Watson was back with his newly adopted baby son - and boy will he have a story to tell him when he grows up.

On Sunday, Watson became the fifth left-handed winner of The Masters in the last 10 years, beating South Africa's Louis Oosthuizen in a play-off after an extraordinary final day at Augusta.

Oosthuizen leapt into the lead by holing a 253-yard four-iron on the second for the first albatross two there in the history of the tournament.

But in the end Watson, the 33-year-old from Bagdad, Florida, won by following four successive birdies on the back nine with a stunning act of escapology on the second hole of sudden death.

Unique in how he likes to hit the ball with massive hooks or slices - "Bubba Golf", he calls it - Watson curved the ball 40 yards from left to right out of the trees and onto the 10th green.

When Oosthuizen, runaway winner of The Open at St Andrews two years ago, failed to save par after coming up short, two putts were good enough and Watson, now the world number four, took them.

Nobody was surprised that Bubba - real name Gerry - blubbed because he has after all his wins, but there was an added reason for the tears this time - his month-old son Caleb.

Watson and his wife Angie started the process of adopting four years ago as she cannot have children.

"It finally came to this winter that we could do it," he said. "We got turned down a couple times, but on the Tuesday of Bay Hill we got a call, on the Wednesday we made the decision and the Monday after we were down in South Florida, picking up little Caleb."

"I can't wait to get back. I haven't changed a diaper yet," Watson added.

On the shot that effectively won him his first major two years after losing a play-off to Martin Kaymer for the USPGA title Watson added: "It just set up for a perfect draw - well, hook.

"I hit about 15 feet off the ground until it got under the tree and then started rising. Pretty easy!"

Asked if he had dreamed about a putt to win The Masters he added: "I dreamed about it - I just never made the putt."

It was only a six-inch tap-in, but Watson thought of Korean IK Kim lipping out from a foot a week earlier in the first of the women's majors and so took his time.

"I wanted to make sure I focused hard on that putt, because I knew how delicate these situations are and how this may never happen again."

Oosthuizen was trying to become the first South African winner in five years after Trevor Immelman and last year's champion Charl Schwartzel.

At least he has a major, though, and he also has the unforgettable memory of his shot on the second.

"That was my first double-eagle ever," he said. "But it was tough the next five holes to just get my head around it and just play the course."

The 29-year-old did a pretty good job of that and was never headed until Watson beat him.

They tied on the 10 under par total of 278, two in front of England's Lee Westwood, Swede Peter Hanson and Americans Mickelson and Matt Kuchar.

Mickelson was left to reflerct on his six at the short fourth, where his tee shot hit the spectator stand and went into the trees.

Rather than going back to the tee, he had two right-handed hacks at the ball and then went into a bunker.

Nobody had won The Masters with one triple bogey, let alone two, and they still have not.

But at least Mickelson had played a far bigger part than Tiger Woods, whose 40th place was his worst finish in the event as a professional.

"You're not going to play well every week," he said. "I had the wrong ball-striking week at the wrong time."

It will be four years since his last major win when he turns up at the US Open in San Francisco in June.