Woods sank two brilliant birdies in the middle of his round
(US unless stated):
-8 T Woods
-7 H Stenson (Swe)
-6 G Ogilvy (Aus), C DiMarco
-5 P Casey (GB)
-4 JM Olazabal (Spa), J Daly
-2C Montgomerie, D Toms, P Harrington (Ire)
+6 L Donald (GB)
Tiger Woods holed two huge birdie putts to grab the lead of the Target World Challenge from Swede Henrik Stenson after Friday's second round.
The American, the world number one, is eight under for the tournament after hitting a four-under-par 68 at California's Sherwood Country Club.
The round included putts of 40 feet at the 9th and 50ft at the 10th.
Stenson carded an eventful 71 to be one shot ahead of US Open champion Geoff Ogilvy and Chris diMarco.
Woods, bidding for his 11th title of the year, was two strokes behind Stenson at the start of the day, and the Swede extended his lead by a further two shots with birdies at the first two holes.
Stenson went on to eagle the 11th but double-bogeyed the 12th, and Woods drew level with a third birdie at the par-five 13th.
Woods then parred the last five holes to move into a slight lead.
World number four finished the day last in the elite 16-player field at 11 over par.
England's Luke Donald, who won the event last year, was only five strokes better off after hitting a 74.