LOS ANGELES — With a flop shot that was amazing even by his standards, Phil Mickelson took a step toward shaking off his West Coast doldrums yesterday with his best round ever at Riviera.

From 40 yards behind the 10th green, his ball buried in the rough and his landing area no bigger than a hub cap, Mickelson's shot barely cleared the bunker and settled 6 feet from the hole to start his day with a birdie.

It sent him to an 8-under-par 63 and a one-shot lead at the Northern Trust Open, a round Mickelson desperately needed after one of the worst starts to his career.

"It was one of the better shots I've hit this year," Mickelson said.

That's not saying much considering this was the first time he has broken 70 on the Left Coast, where Lefty has compiled 16 of his 34 victories on the PGA Tour.

The rest of his game also was sharp. The misses weren't nearly as wild, the putts dropped far more frequently and Mickelson picked up confidence with each of his eight birdies.

"There's three more rounds to go," he said. "But I feel like I'm back on track."

Scott McCarron birdied his last hole for a 64 to give himself another shot at a tourney where he has twice played in the final group without winning.

The group at 66 included Castle High alum Dean Wilson. Punahou alum Parker McLachlin opened with a 75.