Playing in the group with Woods, Phil Mickelson endured three straight bogeys to go to 3-over for the tournament, while Adam Scott was 1-under for the day to move to 1-over for the tournament.
The surprising first-day leaders, Justin Hicks and Richard Streelman, disappeared almost as quickly as they took to the course. Streelman made a triple-bogey 6 on No. 3 en route to a 6-over 77 that left him at 3-over. Hicks made the turn in 39 and was 5 over through 12 holes.
In all, Torrey Pines was looking like the biggest winner, showing its teeth with the kikuya rough moist and tangly and the greens getting firmer. On Thursday, only 11 players broke par, and with the entire field either on the course or done for the day, it looked like that number would dwindle for the second round.
In a strange way, though, the tough set-up produced lots of beneficiaries. With Mediate and Appleby leading at 3-over, the 10-shot cut rule was looking very much in play. Midway through the afternoon round, 84 of 154 players were projected to make the cut.
That included Vijay Singh, who shot 78 to balloon to 7-over but insisted, "I still played really well."
"If you look at the mistakes, it's really silly ones," he said.
Though they were few, good scores were possible.
British Open champion Padraig Harrington shot 4-under 67, the best round of the tournament, to make the cut, and D.J. Trahan and Davis Love III shot 2-under 69. Sergio Garcia had a 1-under 70.
Garcia was 4 over for the tournament while Trahan and Love III were each 1 under. Love was in contention after missing the Masters, ending a streak of 70 straight majors, and getting to the U.S. Open through qualifying.
"If I win the U.S. Open, it doesn't make up for missing the Masters," said Love, the 1997 PGA champion who has been rehabbing from surgery on his left ankle. "It just means that I'm in the Masters the next few years. But that was disappointing."
Woods is seeking his 14th major, which would leave him only four short of the record held by Jack Nicklaus. He is playing his first tournament since the Masters, after which he had surgery to clean out his left knee.
The route through Torrey Pines is no easy walk, as he is finding.
Starting on the back, he opened with a three-putt - the same way he closed his first round Thursday - that put him 2 over. After another bogey on No. 12, though, Woods hit his approach on the par-5 13th hole to 10 feet and made the putt for an eagle.
But he was in bunkers and the rough for most of the rest of his first nine, which resulted in a bogey on 16 and another on 17.
Mediate, meanwhile, started with two birdies over his first four holes and didn't make a bogey until No. 10, when his tee shot bounded down a cart path and into the rough, forcing him to hack into a bunker. He couldn't get up and down and dropped a stroke, to 3-under.
Appleby made birdies on Nos. 7 and 9 to pull into a tie for the lead.
That's where Streelman had been until about 30 minutes into his round, when he dropped off the leaderboard completely with his triple-bogey. He wasn't blaming the course.
"Optimal scoring conditions, I felt," Streelman said. "There are certain places you can't miss the ball on some of these short sides and approach shots and par-3s. And I did that three or four times. You have to pay the price in the U.S. Open."
Among those who had their chances in the morning rounds, but couldn't cash in, were Luke Donald, two-time champion Ernie Els and 2006 winner Geoff Ogilvy, all of whom got to 2-under for a time.
Els closed with two birdies to shoot 72 and finish at even.
Ogilvy shot 73 to also finish at even, failing to make another birdie after he sank a 25-foot downhill putt on No. 5. And Donald made three bogeys on the back to shoot his second straight 71.
"The greens are usually a little more forgiving in the morning, the putts are smoother, and you can control your ball better," Donald said. "Other than that, it wasn't too different."
