SAN DIEGO — One week after he began his year by missing the cut, Tiger Woods didn’t notice a big difference in his game.

It was everything else about the opening round at Torrey Pines that changed. Relatively calm conditions. Rough that didn’t cover the top of his shoes. A course that has been good to him since he was a teenager. And despite his putter not cooperating at the end of his round, a 4-under 68 on his scorecard.

Woods was on the verge of joining defending champion Brandt Snedeker and K.J. Choi atop the leaderboard Thursday in the Farmers Insurance Open until missing three straight putts inside 12 feet late in his round.

Snedeker was bogey-free on the North Course for a 65. Choi birdied three of his last four holes on the tougher South Course for his 65.

Woods, a seven-time champion at Torrey Pines, at least got off the South Course without further damage when he had to lay up on the par-5 18th hole, hit wedge over the green and into a bunker and made a 6-foot putt for par.

Phil Mickelson had quite the taxing day with a 72 on the North, which played about 1˝ strokes easier than the course that hosted the U.S. Open in 2008.

Of the eight players at 66, only Josh Teater posted his on the South Course. Of the PGA Tour events that use multiple courses, few of them are as different as the South and North at Torrey Pines, although the difference in scoring average has been greater in recent years.

Charles Howell III summed it up best after his 66 on the North.

“The real one is tomorrow,” Howell said.

Howell lost in a playoff last week in the Humana Challenge.