On this day, Woods finished before Mickelson and O'Hair sat down for lunch.
After going from bunker to water for a double bogey on the fourth hole, it looked as though Woods might go an entire week without shooting par or better, something he had only done in three majors. But four straight birdies around the turn and a 10-foot eagle on the 16th sent him to a 67 to finish at 288.
"I knew I could shoot a round in the 60s here if I'd just make a few putts, and I did today," Woods said.
Eight players were within four shots of O'Hair at the start of the final round, and that number dwindled quickly when only three of those players - Mickelson, Jose Coceres and Carl Petterson - made a birdie through the first five holes.
Mickelson again met with Harmon for a two-hour session on the practice range some six hours before he teed off, and they worked again before he headed to the first tee. Lefty looked irritated with his first drive, a low, sweeping fade that started out over the water before finding the fairway.
But he wasted no time catching O'Hair.
Mickelson holed a 25-foot birdie putt at No. 1, and O'Hair stayed in the lead by making a 7-footer for par. O'Hair had to make a nervy 4-footer on the next hole to match birdies with Mickelson, and the kid followed with two bunker saves to stay atop the leaderboard.
The start of the back nine turned in Mickelson's favor.
From a fairway bunker, O'Hair bounced his approach over the green and played a full flop that came out strong and went through the green into more rough. He chipped short and made his first bogey to fall one shot behind.
O'Hair appeared to have the advantage on the par-5 11th when Mickelson found the right rough and played a risky shot with a hybrid to the left portion of the fairway. O'Hair had a shot at the green, and his ball came up a yard short of perfect, instead dropping down the slope and into the bunker. It was a simple shot, but O'Hair caught it heavy and settled for par. Mickelson nearly holed his wedge and made a 4-footer for birdie, and suddenly the lead was two shots.
They traded pars the rest of the way, both missing a few good birdie chances.
That gave Mickelson a two-shot cushion playing the island green, one of the few holes were he aims for the middle of the green. That's where he hit it Sunday, leaving the risk - and penalty - to someone else.
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