Tiger Woods found his old Torrey Pines magic to surge to a two-shot lead after the second round of the US PGA Tour.
Starting the day three shots back, Woods fired a seven-under-par 65 on the North course to move to 11-under-par for the tournament, two clear of fellow American Billy Horschel (69, South).
Sharing third at eight-under are Casey Wittenberg (67, North), Brad Fritsch (67, South), Erik Compton (65, North), Steve Marino (68, North), Josh Teater (70, North) and Jimmy Walker (69, South).
John Senden is the only Australian sitting well placed in a tie for ninth after the Queenslander fired a 68 on the North course to move to seven-under.
Woods fired in six birdies and eagle and just a lone bogey to become odds-on favourite for a seventh title at the event having won in 1999, 2003, 2005 and 2006-'08.
The old magic was back for the former world No.1 particularly around the turn where he was five-under in a four-hole run.
The 14-time major champion also won the 2008 US Open on the same venue.
"I played well today. I drove the ball great and took advantage of the par fives," Woods said.
"I've been able to dedicate more time to my short game and, consequently, it's better. I feel good right now."
Senden made a sizzling start with a six-foot bending birdie putt on the first and added a 15-foot effort on the fifth and a 12-foot make on the seventh.
When he dropped in a five-foot putt on the ninth, he was in a tie for second place and looking hot.
But what had been constant light drizzle turned to heavier rain and his form cooled on the back nine, making his lone bogey on the 13th after a heavy chip before getting the shot back on the 17th with a precision seven iron to five feet.
"I felt good out there and I'm looking forward to the weekend," Senden said.
"As the conditions got worse, I kind of felt like I was just hanging on but it was good to keep myself in it and I struck the ball better off the tee today which was nice.
"There are low scores out there and I'm striking the ball well so I need to attack the soft golf course tomorrow."
In a poor day for the 14-strong Australian contingent, only Scott Gardiner, Aaron Baddeley and Jason Day joined Senden in making the cut but the trio sit 10 adrift of Woods at one-under.
Marc Leishman, Cameron Percy, Stuart Appleby, Rod Pampling (all even), Steven Bowditch (+2), Alistair Presnell (+3), Greg Chalmers (+3), Matt Jones (+4) and Geoff Ogilvy (+6) head home early as does Robert Allenby who withdrew midway through his round with a left hip injury.
-AAP