Woods eagled the par-five second and has a four-shot lead
Tiger Woods extended his lead to four shots at the Chevron World Challenge with an impressive 66 in the second round at Thousand Oaks.
The world number two had one eagle and four birdies as he moved to 13 under.
Northern Irishman Graeme McDowell is in second on nine under, with compatriot Rory McIlroy (70) and England's Luke Donald (66) a shot further adrift.
Paul Casey is another two back after a hole-in-one on the 186-yard 12th helped him to a round-of-the-day 65.
The Englishman hit a disappointing 73 in the opening round but is now fifth in California.
Woods, who posted his best 36-hole score this season and who has not won a tournament this year, said afterwards: "It feels good. I've been here before, so it's not a strange feeling.
"I didn't hit the ball quite as sharp as I did yesterday, but I felt better with the putter. I hit a lot of pure putts, made a bunch of five and six-footers all day today."
The 14-time major winner, who is hosting the tournament, set the tone for his round when he eagled the par-five 2nd and followed that up with birdies on the 4th and 5th holes.
Two further birdies on the back nine kept him out in front but the gap to the chasing group might have been smaller had McIlroy not double bogeyed the last.
US Open champion McDowell, who will be paired with Woods over the weekend, also marked his card with a double bogey on the 9th and said he was happy to finish relatively unscathed.
"Sometimes in a four-round tournament, you get a round where you don't really play your best," he said. "To shoot three under and not play my best, I'm pretty happy with that."