Bubba Watson defeated Tim Clark on the first play-off hole to win the WGC-HSBC Champions on Sunday after an extraordinary finish to the £5.4million event in Shanghai.
Watson was two shots clear with three holes to play at Sheshan International only to bogey the 16th and run up a double bogey on the 17th after failing to escape a greenside bunker at the first attempt.
That dropped the Masters champion one shot behind playing partners Clark and Rickie Fowler, as well as the final group of Graeme McDowell, Hiroshi Iwata and Martin Kaymer.
Clark looked in pole position when he hit his third shot to the par-five 18th to four feet and saw Fowler find the water and Watson a greenside bunker.
However, Watson then amazingly holed his bunker shot for an eagle and Clark's birdie was only good enough to leave the pair tied on 11 under, with the final group needing to birdie the last to join the play-off.
Kaymer's chances disappeared when his approach flew over the green into the water, while McDowell and Iwata missed from 18 and 12 feet respectively.
Clark and Watson returned to the 18th for the play-off and Watson found the same greenside bunker with his second shot after Clarke had hit his third to around 20 feet.
Watson was unable to repeat his heroics from the sand but after Clark had left his birdie attempt short, the left-hander holed his birdie putt to seal victory.
"For me this is the big one," Watson said after his third win in 2014. "It's very big because I always wanted to win outside the US. It's my seventh win, gets me closer to 10 wins which has always been my goal. It's a World Golf Championship, so when you add it all up it means a lot."
Speaking about the 72nd hole, the 36-year-old added: " It was such a tough bunker shot you are not really thinking about making it, but I told my caddie it's been a wild day, a wild couple of holes, but if we can make this it changes everything and it went in like a putt. Clark was like 'Why would you do that?!'
"In the play-off, it was f unny because the bunker shot I holed was on the same line (as the putt) so we knew the line, we knew it was fast. I was trying to two-putt and it just fell in."
Clark was left to rue missing a short birdie putt on the 16th but the South African said: "I n ever expected to be in this position at the start of the week. I fought hard. I knew I needed to birdie that play-off hole, especially with him (Watson) being able to reach.
"Obviously disappointed to be that close but I'm pleased overall. I just tried to play this course smart and in the end it was enough to give me a shout."
McDowell had led since an opening 67 but struggled to a closing 73 to finish joint third alongside Iwata and Fowler, who saved par on the 18th in a round of 70.
"To be brutally honest, I didn't have my 'A' game all week," McDowell said. "And the golf course just got so difficult this weekend. The pins were evil at times and you really had to be on your iron play to have a chance to access them and I didn't play well enough, simple as that.
"The putter that was so hot early in the week kind of cooled off this weekend, but to finish T-3 in this type of field, not playing my best, I have to count myself fairly fortunate.
"To finish third in the style I did, I'm disappointed. To finish third playing the way I did, I'm pretty happy."
US Open champion Kaymer also tried to look at the positives despite the double bogey on the 18th which dropped him into a tie for sixth with Ryder Cup team-mate Ian Poulter and Denmark's Thorbjorn Olesen.
" I t was just unfortunate with 18," said Kaymer, who won the title in 2011. "Thought I had a good yardage. I thought it was a perfect yardage with a hurting wind, but it came off very, very hot.
"But I take a lot of positives out of that week. It was a good week. I played really well and I have another two or three big tournaments to go."