Woods, however, only squee-zed past Ian Woosnam at the 37th and, coughing and spluttering as he tries to shake off a cold, admitted it had been an "exhausting battle". Two down with three to play, Woods made one of his customary Houdini acts, aided by some putting lapses by the Welshman.
Woosnam three-putted at both the 16th and the 18th, missing from three- feet at the first and, after holing from 15 feet to go down the last one up, from four-and-a-half for the match. "I made some mistakes but so did Ian and he let me slip in," Woods said.
Thinking he needed an eagle three at the last, Woods found the front of the green with his second but his first putt came up just short. "I thought it was over then," he admitted.
But given another chance, Woods got up and down from the back of the green at the first extra-hole, while Woosnam failed to do so from in front. The Welshman had been three-up after eight in the morning and was still ahead at lunch. Woods was never at his best but an exquisite chip-in at the fourth put him one-up. Woosnam, though, would not give up and when the American went out of bounds at the 12th, he had lost four out of five holes.
Westwood also had to recover after losing the first four holes after lunch and from two down after seven. At the turn, having played the front nine in 38, the 25-year-old told himself it was time to make some birdies. Soon he returned to the form that saw him round in an approximate 65 in the morning, but only after Els missed a three-footer at the 11th.
At the next, a par-five, Westwood hit a three-wood from 236 yards to two feet: "One of my best shots for a long time," he said. He also birdied the 13th and the 16th. "When Lee got me up against the wall, he finished me off," admitted Els, who had not departed before the final in his four previous appearances in the event. "Lee is the guy to beat right now. He plays so well when the pressure is on."
"That is a great compliment given the quality of the field," Westwood said. "I feel I am playing well." Until the starter went through Els' record in the event on the tee, Westwood was not aware of quite how good it was. "I am delighted to beat Ernie, no matter what tournament but especially on a course and in a tournament he has made his own."
The other semi-final features a pairing with three of the four major titles for the year after Vijay Singh ran away 7 and 6 over Patrik Sjoland and Mark O'Meara beat Colin Montgomerie 5 and 4. "If Vijay shoots 62 in the morning again, I'll caddie for him in the afternoon," O'Meara said.
Having sat out the opening day for the first time, Singh was eager to get going and once he had birdied the first, there was no stopping him. "Every bit of my game was on song," he said. Sjoland did not know what had hit him.
His four birdies in the morning were not good enough to win a hole, and he even lost the fourth to an eagle from Singh after a four-iron to two feet. His seven-up lead at the turn was a record and only Ronan Rafferty in 1990 had achieved 10-under for 18 holes before.
Singh, remembering a tip from Seve Ballesteros that if "you get 10-up, go for 11", moved to that score after three holes in the afternoon, at which point the record winning margin of 11 and 9 by Tom Watson over Dale Hayes in 1978 was in danger.
From there, however, Sjo-land birdied six of the next nine, not that the Fijian was worried in the slightest. "It was just a matter of time," Singh said.
Montgomerie was three-up after 16 holes, but then lost nine of the next 12. O'Meara finished birdie, eagle, to cut the deficit to one, but Montgomerie thought the key moment was when he duck-hooked his drive at the third. "I only hit one fairway with my driver in the morning and one in the afternoon.
"I handed him the third, fourth and fifth and then he relaxed and started playing like the Masters and Open champion he is."
QUARTER-FINALS (Seeded positions in brackets):
(1) V Singh (Fiji) bt P Sjoland (Swe) 7 and 6
(4) M O'Meara (US) bt (5) C Montgomerie (GB) 5 and 4
(6) L Westwood (GB) bt (3) E Els (SA) 2 and 1
(2) T Woods (US) bt I Woosnam (GB) at 37th
TODAY'S SEMI-FINALS AND TEE-OFF TIMES:
0830 and 1245 (1) V Singh (Fiji) v (4) M O'Meara (US)
0845 and 1300 (6) L Westwood (GB) v (2) T Woods (US)Reuse content