California - Camilo Villegas and David Toms delivered bogey-free nine-under rounds on Thursday to share a one-shot lead after the first round of the US PGA Tour's $5.6 million Humana Challenge.
On a day when low scores were plentiful, Villegas grabbed nine birdies on the Nicklaus Private Course and Toms nabbed nine birdies on the La Quinta Country Club layout as they topped the leaderboard on 63.
South Korean Bae Sang-moon, a newcomer to the US tour this season, was among the group chasing on 64, along with Ted Potter, Brandt Snedeker and Bob Estes.
Both Toms and Villegas said they benefitted from some time off after last season, and Toms certainly looked fresh as he played alongside Phil Mickelson in front of a large gallery in the tournament formerly known as the Bob Hope Classic.
Playing at La Quinta, the toughest of the three courses used for the event, Toms drained a 30-foot birdie putt at the sixth.
"That's probably the biggest crowd I've ever had playing golf here," Toms said. "It was nice to play a good round and have people energized and out there cheering for your birdies."
Mickelson eagled the sixth, but eventually settled for a 74 in a round marred by a triple-bogey seven at the par-four 14th. However, he didn't sound too discouraged.
"I use this week as a week to get my game, kind of assess it, get it sharp, and it's great that we have these fun golf courses and perfect weather that allow me to see where some weaknesses are," Mickelson said.
"And I made a few loose swings with the driver which I thought I had ironed out heading in, but I'm going to go head over to the range now and work on that, because I don't feel like it’s far off, even though it looked like it was."
Villegas, who endured a disappointing 2011 season, said he took a long break in Colombia and at his Florida home.
"You feel that you're a little rusty, but at the same time, you're mentally fresh," said Villegas, who has won three US PGA Tour titles. "It's a funny game. Sometimes being mentally fresh is more important."
The tournament, which has been shortened from its former five rounds to a more traditional four, is being held in partnership with the Clinton Foundation to promote healthy lifestyles.
Former US president Bill Clinton, who will play alongside Australian great Greg Norman on Saturday in the revised format for pairing pros with amateurs, was on hand on Thursday.
Norman, playing here for the first time since 1986, carded a 72.
"Nothing really worked," said Norman, who was making his first US tour start since 2009. "It was just pure rust, that's all it was. Just rusty, rusty, rusty."
Along with Mickelson, and Norman -- who draws plenty of fans no matter how rusty his game -- the field includes defending champion Jhonattan Vegas of Venezuela and world number eight Dustin Johnson.
Conditions were perfect in the California desert east of Los Angeles and it showed in many scores.
Potter made five straight birdies on his back nine, while Estes, a 45-year-old who hasn't won since 2002, grabbed a share of third place with a birdie-birdie finish.
Leading first-round scores here on Thursday in the US PGA Tour $5.6 million Humana Challenge on the Arnold Palmer Private Course and Jack Nicklaus Private Course at PGA West and La Quinta Country Club (USA unless noted, all par-72):
63 - David Toms, Camilo Villegas (COL)
64 - Bae Sang-moon (KOR), Bob Estes, Ted Potter, Brandt Snedeker
65 - Kevin Chappell, Chad Collins, Ben Crane, Mathew Goggin (AUS), Steve Marino, Noh Seung-yul (KOR), Brendon de Jonge (ZIM)
66 - Blake Adams, Stephen Ames (CAN), Bud Cauley, Gary Christian (GBR), Martin Laird (GBR), Kevin Na, Brendon Todd, Mark Wilson
67 - Michael Bradley, Erik Compton, Ken Duke, John Mallinger, William McGirt, Jeff Overton, Pat Perez, Brett Quigley, Bo Van Pelt