SAN DIEGO — Even with a sore knee, Tiger Woods hit his stride Friday at the U.S. Open.

It started with his feet on a concrete cart path and a shot that went under a tree and over a bunker to 18 feet for birdie. What followed was flawless golf and a 30 on the front nine at Torrey Pines that gave Woods a 3-under 68 and left him one shot behind Stuart Appleby going into the weekend.

Appleby holed a 45-foot birdie putt on the 18th hole for a 70 that gave him the lead in a major for the first time since he led Woods by one shot going into the final round of the Masters last year.

Appleby was at 3-under 139 and will play in the final group with Rocco Mediate, who seems to play his best golf in the toughest conditions. Mediate reached 4 under at one point before settling for a 71, also one shot behind.

Woods will play with Robert Karlsson, whom he defeated in a meaningless singles match at the Ryder Cup two years ago. Karlsson had a 70 to join the others at 140.

"He wants to play some golf, we want to play some golf," Appleby said, and then he joked: "I just know I'll be doing the best I can to actually throw a club toward his sore knee. It'll be an accident, of course."

Phil Mickelson had trouble keeping his 3-wood in the fairway, made six bogeys and shot 75 to fall seven shots behind.

Appleby, Mediate and Karlsson were jostling for the lead throughout the afternoon, and Appleby finally grabbed it on his final hole. He recovered from back-to-back bogeys early on his back nine with birdies on the par 5s, the last one from below the ridge that put him atop the leaderboard and left several players more than 10 shots out of the lead and out of the tournament.

Woods was on the opposite side of the course, and despite the famous "June Gloom" layer of fog that blanketed Torrey Pines, he was easy to find. A high-charged gallery, crammed in the bleachers and behind the ropes, rose to their feet with every birdie.

"All of a sudden, they just started flying in from everywhere," Woods said.

After his approach shot just inches from the cart path on No. 1, he never missed another fairway or another green. Woods poured in a 20-foot birdie on the second hole, then rolled one in from 25 feet up the slope on No. 4, putting him at even par for the tournament.

One hole later, his downhill putt from 18 feet broke sharply toward the ocean over the final inches and dropped into the heart of the cup, bringing another light fist pump and a red number on the board. He was under par.

He finished his round with a fairway metal that hung in the gray skies and landed on the green at the par-5 ninth, running just over the back. Woods chipped to 6 feet and made the birdie, just moments after Appleby had made his on the 18th.

"I was just hanging around, hanging around," Woods said. "This golf course will bite you quick. You've just got to hang in there and stay patient."

Woods almost always bites back at Torrey Pines, where he has won the Buick Invitational a record six times. This one is far more meaningful, and his late charge left him in great position to chase a U.S. Open title that has eluded him since 2002 at Bethpage Black, the last time it was held on a municipal golf course.

Mickelson, a San Diego native and three-time winner at Torrey Pines, could not keep up in the featured pairing with Woods.

He again played without a driver in the bag, and this time it might have hurt him. Lefty could not reach the par-5 13th, where Woods got home in two and made eagle, and he was 30 yards behind Woods on the sixth hole, putting his approach on the tongue of a bunker that led to one of his six bogeys.

Mickelson was at 4-over 146 and in a tie for 35th in a hometown U.S. Open he called a "once in a lifetime" chance.

Only eight players remained under par on a city-owned golf course that has been universally praised as fair — a word seldom heard at the U.S. Open — but not necessarily easy.

Woods and a few others only made it look that way.

Miguel Angel Jimenez of Spain made a quiet charge, and his birdie on the par-5 ninth — three groups behind the circus following the top three players in the world — gave him a tournament-best 66. He was at 1-under 141, along with Lee Westwood of England (71), Davis Love III (69) and D.J. Trahan (69).

"If you're 1 under par through two rounds in a U.S. Open, you're doing something right," Trahan said. "Like anybody will tell you, this isn't a birdie contest. This is a survival contest."

Woods was in that survival mode early, three-putting from long range for bogey on No. 10 and hitting his approach into the right rough for another bogey on No. 12. He was sliding down the leaderboard until smashing a drive on the 614-yard 13th hole — with the tee pushed all the way back — and hitting a fairway metal to 10 feet for eagle.

But the momentum was shifting as quickly as clouds replaced patches of sunshine along the Pacific.

He fell back with consecutive bogeys from the bunker on the 16th and 17th holes and hit yet another bunker off the tee on the 18th, taking an easy birdie away. And his drive on No. 1, his 10th hole, was well right, which worked in his favor. Instead of being in the ankle-deep kikuya grass, it was just inside the cart path on a clean lie.

The 8-iron from 157 yards was pure, and so was the birdie putt. Just like that, Woods came to life and hardly looked like a guy who had been gone from tournament golf for two months.

"Whether you call it a zone or not, I got into a rhythm," Woods said. "I've been there before. I've had nice rounds like that. I was just trying to get back to even par. I just happened to make some putts. That was it."