Updated

The scoreboard at Torrey Pines for the Farmers Insurance Open was filled with names followed by "NC" in parentheses.

That stands for the North Course.

It might as well have meant "no contest."

Spencer Levin, with one key shot out of a bunker that changed his outlook, shot a 29 on the back nine for a 10-under 62, matching his best score on the PGA Tour. Kyle Stanley played his final seven holes in 7-under par, closing with an 8-iron into the par-5 18th green for eagle and a 62 that was his lowest score in two years on the PGA Tour.

Bill Haas made a double bogey and still shot 63, courtesy of his 11 birdies.

It was no surprise Thursday that the top 12 players on the leaderboard all played the North Course, which is 604 yards shorter than the South Course, site of the 2008 U.S. Open. When the toughest test in golf came to Torrey Pines, the North Course was used for parking, practice areas and corporate tents.

"I played the pro-am on the North Course yesterday. There were just a lot of birdie opportunities out there, so I knew there was a good score — maybe not 10 (under), but I'll take it," Stanley said.

The first-round leader almost always is on the North Course. Tournaments aren't won on the opening day of this tournament, though they can easily be lost. That's why Rod Pampling was happy with his 64, and when asked if the tournament really doesn't start until Saturday when players have been around both tracks, he replied, "I guess. But you can certainly take yourself out of it."

The average score on the North was 69.24. The average score on the South was 72.85.

The best score from the South was Marc Turnesa at 66.

Phil Mickelson, meanwhile, went south on the South. The three-time champion and San Diego favorite thought his game was rounding into form when he came home from the Humana Challenge. Instead, he hit into 11 bunkers, missed a 3-foot birdie putt on the final hole and signed for a 77. It was his highest score at Torrey Pines since a 78 in the third round of 2005.

"Obviously, I made some bad swings just in the wrong spot and so forth," Mickelson said. "I felt like my game was ready heading in, and I don't know what to say about the score. Because it was pathetic."

A year ago, the fairways were pinched in and the rough was unusually high on the North Course, helping to make up for the 604-yard difference between the two courses. Based on the scores, that's no longer the case.

Pampling, Vijay Singh, Josh Teater and PGA Tour rookie John Huh were at 64, with Huh making three eagles. Camilo Villegas and Justin Leonard were among those at 65.

Of the 54 players who shot in the 60s, only 13 of them were on the South Course. One of them was Paul Goydos, who doesn't buy into the theory that with two vastly different courses, the tournament really doesn't start until Saturday when everyone has played both.

"Ten under is leading the tournament, and anyone who says differently is full of it," Goydos said. "I looked at the leaderboard."

He would argue that some players simply have better vibes on the different courses. What might be a big difference to one player might be much less to another.

"All I know is that I'm six shots back and I've got to deal with it," he said.

One thing that left little room for debate — the weather could not be any more gorgeous for late January along the Pacific coast, a day of endless sunshine and warm temperatures that made even the South play a little shorter.

Levin noticed only one big change in his game, and that was putting the ball in play. That made quite the difference, for hit set up short irons and plenty of birdie opportunities.

"I had some putts for birdies instead of pars, and kind of added up to a good score," Levin said.

The turning point came when Levin thought he might made bogey. He drove into the bunker on No. 7, leaving him an uphill shot to a difficult green, blocked partially by a tree.

"I was thinking I wouldn't have a shot. I was thinking it's probably going to be a bogey, and I'll go back to even (par)," Levin said. "I cut an 8-iron around and go on the right side of the green and hit a 20-footer — it probably broke 10 feet — and I made it. So it felt like at least a one-shot swing."

He followed with a birdie on the par-5 ninth, and making the turn at 3 under instead of 1 under changed everything for him.

Haas, coming off a sluggish start in Kapalua and the California desert, was at 8 under with four holes to play when he missed the green well to the right on the picturesque, downhill, par-3 sixth hole. His long pitch from the rough didn't reach the green, he chipped some 15 feet past the hole and made double bogey.

That made him upset.

He finished with two strong birdies, which eased the sting and could lead to some momentum on Friday.

"I would love to be 10 or 11 under," Haas said. "But to get over that and finish with two good birdies, I was pleased with that."