* American left-hander claims first major title

* Edges out Oosthuizen at second extra hole

* Woods exits with worst Masters finish as a pro

(Adds detail, quotes)

April 8 (Reuters) - American Bubba Watson conjured a

miraculous par from pine straw to become only the third

left-hander to win the Masters with an emotional playoff victory

over Louis Oosthuizen at Augusta National on Sunday.

Watson clinched his first major title with a two-putt par on

the second extra hole, the par-four 10th, where South African

Oosthuizen bogeyed after ending up just short of the green in

two and failing to get up and down.

Both players had ended up well right off the tee, Oosthuizen

gaining a fortuitous bounce off a tree before playing his second

shot from the first cut of rough.

Although the long-hitting Watson ended up deep in the tree

line, he had an avenue to the green and struck a superb high

draw off the pine straw for his ball to settle 10 feet from the

pin.

After Oosthuizen had chipped up 15 feet past and narrowly

missed his par putt coming back, Watson had the luxury of two

putts for victory.

His birdie attempt slid past the cup but the 33-year-old

from Bagdad in Florida gathered himself and tapped in for

victory before embracing his caddie.

"I never got this far in my dreams," a teary-eyed Watson

said in the Butler Cabin before being helped into the prized

green jacket by last year's Masters champion Charl Schwartzel of

South Africa.

"It's a blessing," Watson added, after joining fellow

left-handers Phil Mickelson (2004, 2006 and 2010) and Canadian

Mike Weir (2003) as Masters winners.

Asked to explain how he had pulled off his stunning approach

on the second playoff hole, Watson replied: "I had a good lie,

had a gap where I had to hook it 40 yards or something.

"I'm pretty good at hooking it, so I just hooked it up there

and somehow it nestled close to the hole."

Oosthuizen, the 2010 British Open champion who had earlier

spectacularly grabbed a two-shot lead with a stunning albatross

two at the par-five second, paid tribute to Watson.

"We had a great day," Oosthuizen told reporters. "It's fine,

he had an unbelievable shot there. I played well ... but great

stuff from him and he deserves it."

The duo had finished the regulation 72 holes on 10-under-par

278, Oosthuizen carding a three-under 69 and Watson drawing

level with four consecutive birdies from the 13th on the way to

a 68.

British world number three Lee Westwood birdied four of the

last six holes for a 68 to share third place at eight under with

Americans Mickelson (72) and Matt Kuchar (69), and Swede Peter

Hanson (73).

WORST FINISH

Four-times winner Woods made a humbling exit from the

tournament after battling his way to a two-over-par 74 and a

five-over total of 293, his worst Masters finish as a

professional.

Woods finished level with U.S. Open champion Rory McIlroy

(76) in a tie for 40th despite the pair being labelled by some

media as tournament favourites in a "two-horse race".

On a glorious sun-splashed afternoon, cheers echoed around

the Georgian pines as the fans were treated to dazzling

shot-making and a few unexpected blunders with five different

players holding at least a share of the lead.

While American Bo Van Pelt and Australian Adam Scott each

recorded a hole-in-one, Oosthuizen sparked some of the loudest

roars ever heard at Augusta with his remarkable albatross at the

second, where he holed out from 253 yards with a four-iron.

The gap-toothed South African watched as his ball pitched

just short of the green before bouncing and then rolling some 50

yards and curving left to right before dropping into the cup.

Oosthuizen thrust both arms skywards before high-fiving his

caddie, having recorded the first albatross, or double-eagle, at

the second hole and only the fourth ever at the Masters.

Although Oosthuizen bogeyed the fourth and the 10th for his

lead to be cut to one, he regained control with birdies at the

13th and 15th before being caught by the charging Watson.

Fan favourite Mickelson had been one stroke behind overnight

but he left himself with too much ground to make up after an

adventurous triple-bogey at the par-three fourth.

After pushing his tee shot into bamboo shoots left of the

green, the American hit two poor right-handed shot then struck

his fourth into a bunker from where he got up and down for a

six.

Woods rued his tendency to allow old habits to creep back

into a swing he has grooved with coach Sean Foley over the last

two years.

"This is a golf course you just have to dominate the

par-fives, and I did not do that at all this week," the 14-times

major champion said after mixing five bogeys with three birdies.

"I fall back into the same old patterns again and I just

need to do more reps. Thank God my short game was good this week

and my putting was really good. Unfortunately they were all for

pars, not for birdies."

(Reporting by Mark Lamport-Stokes; Editing by Nick Mulvenney)