Ogilvy is in the semifinals for the third time in the last four years.
MARANA, Ariz. (AP) -- Geoff Ogilvy played his best golf of the week Saturday, making five birdies on the back nine to hold off teenager Rory McIlroy, 2 and 1, and advance to the semifinals in the Accenture Match Play Championship.
Ogilvy, who reached the semifinals for the third time in four years, faced Stewart Cink in the afternoon.
Cink played his shortest match of the week in beating Ernie Els, 2 and 1. The American went to extra holes the first two rounds, and defeated Phil Mickelson in 18 holes Friday.
"I keep playing less and less," Cink said. "That's either a good thing or a bad thing."
Paul Casey didn't have to break much of a sweat in taking advantage of poor play from Sean O'Hair, who shot a 40 on the front nine and fell hopelessly behind. Casey, who won the World Match Play Championship in England in 2006, won 4 and 3.
In an all-England semifinal, Casey will take on Ross Fisher, who beat Justin Leonard, 2 and 1. That guarantees England a spot in the championship match for the first time in the 11-year history of this event.
McIlroy, the 19-year-old from Northern Ireland who won last month in Dubai, had hopes of becoming the youngest champion in American professional golf history. Johnny McDermott was about three weeks older when he won the 1911 U.S. Open.
But he ran into one of the toughest players in this format.
Ogilvy, who won in 2006 and lost in the championship match a year later, was 7 under when the match ended on the 17th hole with another clutch putt, this one from 12 feet.
McIlroy was at times 50 yards or more longer than Ogilvy off the tee, but the Australian was the one who applied constant pressure. Ogilvy never trailed after the fifth hole, when he hit his approach from 200 yards into 15 feet.
The match really came down to one bad swing.
Tied standing on the 11th tee, McIlroy was uncomfortable with a tee box moved some 100 yards forward, making the par 5 play only 556 yards in the high desert air. He hooked his tee shot into a desert bush, the ball dangling 6 inches off the ground. McIlroy took a penalty drop and missed a 12-foot par putt, giving Ogilvy the hole.
On the par-3 12th, he knocked in a 15-foot birdie to seize control of the match. Still, it was hard work.
"I birdied the last three holes and only won one of them," Ogilvy said. "I had to play well today. He's the real deal. He's going to be around for a while."
McIlroy now heads to the Honda Classic with his confidence growing.
"I can take a lot out of this," he said. "It was a great week under pressure. I couldn't have done much more against Geoff."
Cink was blown out in the championship match last year by Tiger Woods, 8 and 7, but he won't have to worry about the world's No. 1 player this week. Woods lost in the second round to Tim Clark, making it a brief return from being eight months away after knee surgery.
The American squared the match with a great up-and-down birdie on the second hole, took the lead on the fourth with a bunker shot from 90 yards that he skipped up a steep slope, and he was in control the rest of the way.
Casey never had to putt a 6-foot birdie on the first hole or his 8-foot eagle on the second hole as O'Hair struggled. The Englishman won three more holes with pars on the front nine, and when O'Hair finally got his game turned around, it was too late.
Fisher beat a U.S. Ryder Cup player for the second straight day -- Jim Furyk on Friday, then Leonard. The match turned on the 14th hole when Fisher went bunker-to-bunker and saved par, while Leonard missed an 8-foot par.
Leonard, who reached the semifinals last year, birdied the next two holes to stay in the match until missing a 5-foot birdie on the 17th. Fisher made his short birdie to close out the match.
Along with being an all-England match, Casey and Fisher have played the fewest holes of anyone this week. Through four rounds, Fisher has played only 63 holes, and Casey has played 65.