KAPALUA, Hawaii (AP) -- Geoff Ogilvy ran off three straight birdies on the back nine and shot an 8-under 65 on Saturday to make the rest of the winners-only field at the Mercedes-Benz Championship feel as though they were playing for second.

The wind switched directions, making the Plantation Course at Kapalua play entirely different. What didn't change was the guy atop the leaderboard.

Leading by one shot to start the third round, Ogilvy played bogey-free for the second time in three rounds and wound up with a six-shot lead over Justin Leonard and D.J. Trahan as he tries to win the PGA Tour's season-opening event.

Leonard made eight birdies over his final 14 holes on his way to a 65, the kind of round that he thought would give him a chance to win. But he never had a good look at the leaderboard until he walked onto the 18th green and saw that Ogilvy was at 19 under.

"It was a little deflating, to say the least," Leonard said.

Trahan was one shot behind Ogilvy and simply couldn't keep up and shot a 70.

About the only thing Ogilvy did wrong was fail to convert three reasonable birdie chances on the closing holes, including the 18th, the only par 5 he failed to birdie in the third round.

He was at 19-under 200, the second-largest 54-hole lead at Kapalua behind David Duval in 1999.

"It's never over until the last hole," Ogilvy said. "I've never had a lead like this going into Sunday, so it will be a new experience for me."

It might be a new course, too.

While the Kona wind brought significant change in club selection, the forecast includes a big thunderstorm approaching the islands, leading the Tour to move the starting times up some three hours.

Even so, this is Ogilvy's to lose.

Camilo Villegas had to scramble for a double bogey on the opening hole, rattled off eight birdies in a 10-hole span and somehow scraped together a 66. That still left him seven shots behind, along with Davis Love III, Kenny Perry and Anthony Kim, who each had 68s.

No one was more frustrated than Ernie Els.

He had a pair of three-putts on the front nine, missed a birdie putt inside 4 feet and finished with 34 putts for a 73. The Big Easy started the day two shots out of the lead, and goes into the final round as an also-ran, 10 shots behind.

Els, Adam Scott (73) and Ryuji Imada (74) were the only players in the 33-man field who failed to break par.

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