Hunter Mahan shot an impressive 2-under 69 in the third round.(Miralle/Getty Images)

Garcia had shot a 1-under-par 70 and moved to within six of 36-hole leader Stuart Appleby, who had yet to tee off.

All Mahan did was go one better, firing a 2-under 69, his first sub-par round in the U.S. Open. That put him not only one step ahead of Garcia, but also a step closer to the top in the 108th U.S. Open.

Tied for sixth place at 2-over 215 at Torrey South, Mahan is proving once again that U.S. Golf Association events are his kind of golf. They must be. He had come into this championship having badly missed the cut in his last two starts after withdrawing from THE PLAYERS with an illness.

"I like this style of golf," said Mahan, 26, who won the 1999 U.S. Junior Amateur and finished second to Ricky Barnes in the '02 U.S. Amateur. "It's penalizing bad shots, but it will reward good shots. And I like that. I like the fact I can step up there and hit a lot of fairways and greens and give myself a lot of good chances and shoot even par and move up the leaderboard.

"Any time you shoot in the red numbers at a USGA event, you're doing something right."

It's not often that a player can legitimately say he left shots on the golf course at a U.S. Open, but Mahan certainly had chances to go even lower. He hit it inside 12 feet on three of his last four holes but only had one birdie, at the 18th, to show for it. And that final salvo was set up by a nifty chip shot from an awkward lie just outside the left bunker.

"Overall, I can't be too disappointed," said Mahan, playing in just his third national championship. "I had another good day. I hit a lot of fairways and greens. At the Open, that's easy to say but hard to do, so I'm playing better than I have been. I just enjoy playing majors and especially the Open."

Mahan, who tied for 13th last year at Oakmont Country Club, enters the final round five behind leader Tiger Woods, who has never lost a 54-hole overnight lead in a major championship. It's a tall order, but Mahan is relishing the challenge of a final-round chase.

"I just have to come out and play ... hit the fairways out there, keep playing smart," he said. "If I put the ball in play off the tee I can play, I can use my irons to my advantage and put the ball where I need to put it. I've got a great feel for these greens. So I'm looking forward to tomorrow, looking forward to the challenge."