LA JOLLA, California, Jan 25, 2013 (AFP) - Playing on the Torrey Pines layout where he has won this event six times and where he captured the most recent of his 14 major titles at the US Open in 2008, Woods had an eagle, six birdies and just one bogey on the North Course.
The 37-year-old, who has struggled with injuries and whose form slumped after an infamous sex scandal in 2009, opened with a four-under 68 on Thursday on the South Course and started the second round three shots off the pace.
He teed off Friday on the back nine and began with four pars in a row before a birdie at the par-5 14th hole.
He scored a birdie at the par-3 17th, an eagle at the par-5 18th and then added birdies on the par-5 first and par-4 second holes, lifting himself into sole possession of the lead.
Woods, now back at number two in the world rankings, birdied the par-4 seventh, took his lone bogey of the round at the par-4 eighth and finished his round with a birdie at the par-5 ninth to stand on 11-under par 133.
Billy Horschel carded a three-under 69 on the South Course to take second place on his own on 135.
Two-time heart transplant recipient Erik Compton was among half a dozen players on 136.
Compton had six birdies and an eagle in a seven-under 65 on the North Course. He was joined on eight-under by Casey Wittenberg (67), Canadian Brad Fritsch (67), Steve Marino (68), Jimmy Walker (69) and Josh Teater (70).
The 87 players who made the cut will play both weekend rounds on the South Course, where Woods gained his memorable US Open triumph five years ago after a playoff with Rocco Mediate, won despite a serious knee injury.
Woods is coming off a season debut at Abu Dhabi at which he missed the cut after taking a penalty for an improper drop.
The key for him at Torrey Pines, where rain fell for much of Friday, has been the par-5s, which he played in 5-under par on Friday and 4-under on Thursday. Altogether he has made five birdies and two eagles to lead the field in scoring on those holes.
"That's basically where the round could be had," Woods said.
"On the North Course, drive the ball well here and you're going to probably have 4-iron shots into the par-5s."
Woods said his short game continues to improve, now that he has bedded-in the swing changes that have taken up a lot of practice time.
"That's something that I needed to work on, and as you saw toward the end of last season, it started coming around," Woods said of play in and around the greens.
"I haven't had to hit as many golf balls, so I've been able to dedicate more time to (it) and consequently, it's better."
Leading scores on Friday after the second round of the $6.1 million US PGA Farmers Insurance Open at Torrey Pines (USA unless noted, par-72):
133 - Tiger Woods 68-65
135 - Billy Horschel 66-69
136 - Casey Wittenberg 69-67, Brad Fritsch (CAN) 69-67, Erik Compton 71-65, Steve Marino 68-68, Jimmy Walker 67-69, Josh Teater 66-70
137 - Nick Watney 69-68, Luke Guthrie 68-69, John Senden (AUS) 69-68, Tag Ridings 67-70, Charlie Wi (KOR) 71-66, Justin Hicks 67-70, Ross Fisher (ENG) 66-71
138 - Charles Howell 66-72, Harris English 68-70, KJ Choi (KOR) 65-73, Bill Haas 69-69, Jim Herman 69-69, Graham DeLaet (CAN) 68-70. Will Claxton 69-69, Jerry Kelly 67-71, Martin Flores 69-69
139 - Pat Perez 72-67, Justin Leonard 68-71, Roberto Castro 71-68, Justin Bolli 72-67, Nicholas Thompson 69-70, Bo Van Pelt 67-72
WD - Robert Allenby (AUS) 76