Zach Johnson got hot on a chilly Southern California day on Thursday to seize a one stroke lead in the World Challenge, with tournament host Tiger Woods four adrift. (Read: I've been influenced by Nelson Mandela, says Tiger Woods)
Johnson, a two-time runner-up in this event, had seven birdies in his five-under par 67. He was one shot in front of Matt Kuchar, whose four-under 68 was highlighted by an eagle at the par-five 11th.
Hunter Mahan and Bubba Watson shared third on 70, followed by Woods on one-under 71 -- the only players in the elite 18-man field for the unofficial event under par.
"There's some tough pins out there," Woods said. "You miss them on the wrong spots, you're going to pay the price, and I think that's kind of what's signified in the scoring. No one is running away with it. Nobody went low today."
After morning frost pushed back tee times one hour, Woods opened with a bogey.
He birdied the fifth and 11th -- both par-fives -- but he missed a golden opportunity at 18 when he missed a four-foot birdie putt.
"I made a few mistakes," said Woods, who hadn't played since a tie for third at the Turkish Airlines Open in early November.
"Obviously the very first hole I missed a little short one, and I missed a short one at 18," Woods said. "But I had a couple good ones on the back nine today end up in some very interesting spots. The golf course is kind of set up that way now."
Johnson and said his only really poor drive cost him his second bogey of the day at the par-four 18th.
"I did everything decent," he said. "I wedged it really good. Any time I had a wedge in my hand, I seemed to be hitting my lines and my yardages. I putted it great. Just a real solid day all around."
Defending champion Graeme McDowell of Northern Ireland, going for a third title in an event he also won in 2010, settled for an even-par 72 that included four birdies and four bogeys.
McDowell played alongside compatriot Rory McIlroy, who notched his first victory of 2013 with a stirring triumph over home favorite Adam Scott at the Australian Open last Sunday but didn't see any momentum carry through in the first round at Sherwood Country Club.
McIlroy had three birdies but four bogeys in his one-over par 73.
McDowell said Sherwood is playing as tough as it has in years as it hosts the tournament for the 14th and final time.
"The course hasn't been this tough in a couple years," McDowell said. "The greens are much firmer. The speed of them caught me by surprise a little bit today. My speed was a little clumsy and it showed today on the greens."