Phil Mickelson was chased all the way to the line in the final round of the WGC-HSBC Champions tournament yesterday before emerging victorious for the second time in three years at the Sheshan International Golf Club.

Most surprising was that the challenge did not come, as expected, from Tiger Woods — who started the day only two strokes behind the world No 2 and in the final group — but primarily from Ernie Els, who let slip while leading by a stroke coming to the last.

Els, who emerged from the pack with a round of 63, found water with his second shot to the par-five 18th and walked off with a bogey that was to cost him dear. He had played brilliantly, but the South African had to settle for second place, one stroke behind Mickelson, who had a round of 69, for a 17-under-par total of 271.

Among the subplots, Rory McIlroy gave his hopes of finishing the year as Europe’s No 1 a tremendous boost with a round that matched Els’s 63 and pushed him 13 places up the leaderboard to fourth. Most importantly, he jumped over Martin Kaymer into second place at the top of the standings for the Race to Dubai and is little more than £50,000 behind Lee Westwood, who finished eighth after a disappointing final round of 71.

Paul Casey, fifth in the standings and playing his first strokeplay event in 12 weeks, pulled out with a recurrence of a rib injury and is now doubtful for the final event of the season, the Dubai World Championship, starting in ten days’ time.

But while all of that was being absorbed, many were left reflecting on a day in which they had witnessed Woods in meltdown. Suddenly the greatest player of them all is looking vulnerable. It probably will not last, but it is surprising nonetheless.

At the Tour Championship in the United States, in September, Mickelson made up a two-shot deficit over Woods on the final day to beat him by three. This time, he did not need to chase. Woods did it all for him.

The two are old adversaries and not the best of friends, so Mickelson will have taken great pleasure in beating the world No 1 so soon after his last victory over him.

From the moment that Mickelson increased his lead with a birdie at the 3rd, things started to go downhill for Woods. The walk to the 4th tee provided a stark contrast. Woods kept his head down while Mickelson, smiling and nodding to the crowds, smacked hands as he went.

And then he slowed down to gather his thoughts. Following behind him was like walking with a boxer to the ring; he was going to make his challenger wait. This, after all, was psychological warfare as much as anything else — not a word was to pass between the two — and within four holes, Woods had gone.

First, he pulled his tee shot at the par-three 4th into water and double-bogeyed the hole — his first putt “lipping” out for the third hole in succession. Then he took three putts from 20 feet at the 6th, the first running ten feet past and the second surprisingly coming up short.

Swishing his clubs in frustration and swearing under his breath, Woods was in poor spirits by the time he was teeing off at the 7th. That a local photographer clicked while he played his shot simply made matters worse. “Jesus Christ, not on my backswing,” he moaned after finding a bunker. From there he advanced the ball no more than five yards and found another bunker with his third. In the end, a bogey was a fair return.

After seven holes, Woods trailed Mickelson by six shots and was out of the running. He rallied well on the back nine but was never in it and suffered the final indignity of finding water at the back of the green at the 18th. His level-par round of 72 left him five shots off the lead and in a share of sixth place. The huge and excitable galleries were undoubtedly a distraction, but it was the same for everybody.

Mickelson was in his element. He had saved par with a putt from the fringe of the green at the 16th and birdied the 17th to take a lead he would not relinquish. Asked by a local journalist if he would be sharing his winning formula with Woods, he could not resist laughing. “Ah, no,” he said, before explaining that Woods needed no help in that department.