|Farmers Insurance first-round leaderboard|
|-6 S Cappelen (Den), K Bradley (US); -5 Byeong Hun An (Kor), J Dahmen (US), K Tway (US), R McIlroy (NI), Xinjun Zhang (Chn), M NeSmith (US), S Im (Kor), B Watson (US)|
|Selected others: -4 J Rahm (Spa); -3 R Knox (Sco), T Woods (US); -1 B Taylor (Eng), M Laird (Sco); level P Mickelson (US); +3 J Rose (Eng)|
World number two Rory McIlroy carded seven birdies and is one stroke off the lead after round one of the Farmers Insurance Open at Torrey Pines.
The 30-year-old Northern Irishman can become world number one with victory this week and returned a five-under 67.
Seven-time winner Tiger Woods, also starting from the 10th on the North course, birdied the last for a 69.
Defending champion Justin Rose is three over, with world number 341 Sebastian Cappelen and Keegan Bradley leading.
Players have a round each on the North and South courses over the first two days before the final two rounds are contested exclusively on the South, where Woods won the 2008 US Open.
The South course will also be the venue for next year’s US Open and 29-year-old Cappelen from Denmark enjoyed himself there on Thursday with eight birdies, overcoming a brief spell of dense fog at the end of his round on the Californian coast.
In his first PGA event of the year, McIlroy holed from the edge of the green at the 18th and played a towering iron shot to six feet at the second to set up a birdie, collecting further birdies on the two par fives of his back nine.
“If I can drive the ball like that for the rest of the week – and the rest of the year – I’ll be pretty happy,” said McIlroy, who won four times last year and has 18 PGA titles.
Masters champion Woods, the world number six, is seeking a record 83rd PGA Tour victory, having equalled Sam Snead’s landmark in his last tour appearance in Japan last October.
“Overall, I’m pleased to shoot in the 60s. The course was gettable today,” the 44-year-old said. “I felt like I hit the ball well, I’m very pleased to get something in the red and get over to south tomorrow.”