PONTE VEDRA BEACH, Fla. - Standing on the 17th tee yesterday in the final round of The Players Championship, Sean O'Hair faced one of the biggest decisions of his young life.

Trailing Phil Mickelson by 2 shots, he could play it safe, shoot at the center of the infamous island green, and go for the par. Most likely, he'd go on to finish alone in second and cash a check for $972,000.

Or he could go for broke. He could fire at the sucker pin tucked in the back right corner, going for a birdie to cut Mickelson's lead. O'Hair went for broke.

"There was no debate," West Chester's O'Hair said of the conversation with his caddie and father-in-law, Steve Lucas. "I went dead after the pin. I didn't bust my butt for four days to get second place. Obviously, I paid for it."

By the time he limped off the 17th with a quadruple-bogey 7, O'Hair's dream of winning his second tournament on the PGA Tour and the so-called fifth major was over.

The result, for all to see, was one of those painful-to-watch catastrophes for which The Players Championship and the 17th are so famous.

Pumped by adrenaline, O'Hair air-mailed the green, and the ball splashed into the water without ever touching land. A second ball O'Hair hit from the drop area trickled off the back of the green into the lake.

Having begun the day as the leader over Mickelson by a shot at 9-under par, O'Hair ended up shooting 76, finishing alone in 11th place at 5 under and cashing a check for $225,000.

On a positive note, he left TPC Sawgrass with no regrets and no apologies.

"Next year, same situation, I'd do the same thing," vowed O'Hair, 24. "I am going to win this tournament."

This time around, the winner was Mickelson, who shot a nearly flawless 3-under 69 to finish at 11 under, 2 shots ahead of Sergio Garcia, who closed with a 66. Stewart Cink, who shot 66, and Jose Maria Olazabal (67) finished tied for third at 8 under.

For Mickelson fans, his 31st PGA Tour victory was cause for enthusiasm and hope. Since he jumped to swing coach Butch Harmon three weeks ago, Mickelson has made once-unthinkable strides in controlling his tee shots. Suddenly, Mickelson's wayward driver is his new best friend. (He hit 10 of 14 fairways yesterday.)

"You're just seeing the tip of the iceberg," Harmon said last night. "He's got as much talent as anybody in the world other than maybe Tiger [Woods], and I think if we can get him out on the fairway, he can rival Tiger."

Last night, Mickelson was already looking forward to the U.S. Open in five weeks. Last year, that was the site of his disaster on the 72d hole.

"In the meantime, I plan on spending some more time with Butch," Mickelson said.

The lefthander also had high praise for O'Hair. "He's a tremendously talented young player, and I have lot of respect for him the way he attacked the back nine and the 17th," he said.

As soon as they teed off in the final pairing, Mickelson began applying pressure, sinking a 25-foot birdie putt that gave him a share of the lead.

When the putt dropped, no doubt along with O'Hair's jaw, it wouldn't have been surprising if O'Hair had begun to wither. He didn't, calmly sinking a slippery seven-footer to save par and prevent a 2-shot swing.

From there, it was game on between O'Hair and Mickelson. With almost everybody in front of them racking up bogeys, not birdies, in the early going, O'Hair and Mickelson found themselves 4 shots ahead, essentially playing match play.

After they both birdied the par-5 second, they swapped pars for much of the front nine. Mickelson grabbed the solo lead at 11 under on the seventh, hitting his approach from 148 yards to 15 feet, then sinking the putt.

The first miscue of the day by either player came at the 10th, when O'Hair carded the first bogey between them.

Trouble started for O'Hair with the tee shot, which caught the fairway bunker that runs up the left side. Then his approach shot air-mailed the green and settled in thick, wiry Bermuda grass rough just off the back. When his full-swing flop rolled off the front of the green, O'Hair dropped to 10 under, a shot behind Mickelson.

The margin widened to 2 shots at the 11th. After missing the fairway, Mickelson laid up, then stuck his pitch-shot approach to four feet, good for birdie.

Like so many players before him over the years, O'Hair found that his Waterloo was the island green 17th.

With the air dead still and the hole playing at only 132 yards yesterday, O'Hair hit a 9-iron - too much club.

Visibly shaken, O'Hair managed to keep his third tee shot on dry land, but the damage was done: The quadruple bogey dropped him to 3-over par for the day. A bogey at the 18th dropped him out of the top 10.

As O'Hair fielded questions about the disappointing finish, Lucas found much to be happy about.

"Nobody wants to finish that way, but I think he is going to gain more than he loses," Lucas said. "Walking up 18, I said, 'I'm proud of you. You did a great job.' Mickelson's caddie, Bones [Jim Mackay], said the same thing. You can't criticize a guy for trying to win the golf tournament."