Putting lets Tiger down at Pebble Pro-Am Fri Feb 10, 2012 8:00pm EST (Reuters) - Tiger Woods was betrayed by his approach play and his putting as he carded a second successive 68 at the Pebble Beach National Pro-Am to finish Friday's second round six strokes off the lead. Contesting his first event on the 2012 PGA Tour, the former world number one mixed four birdies with two bogeys on the par-70 Monterey Peninsula Shore Course, the easiest of the three venues being used this week. Woods found 16 of 18 greens in regulation as early morning sunshine gave way to a mixture of mist and rain but he totaled 33 putts before ending the day at six-under 130, six behind pacesetting South Korean Charlie Wi. "The wind was pretty constant all day which was nice," Woods told reporters. I got sliders or downhill putts and the greens started to get a little bit bumpy because of the softer conditions. The downhill putts just aren't going to go in, so I had to leave myself in better spots than I did. Woods, who won the 2000 Pebble Beach National Pro-Am before returning to the picturesque Monterey Peninsula later that year and clinching the U.S. Open by a record 15 shots, accepted he needed to shoot a low score on Saturday. "I am six back so I need to make something happen a little bit over there," he said of his third round at Pebble Beach Golf Links. There are too many guys between myself and the lead ... so I've got to go get it tomorrow. Having putted well and driven the ball superbly during his four-under opening round at Spyglass Hill on Thursday, Woods was looking to go much lower on the Monterey Peninsula layout to claw his way up the leaderboard. Watched by huge galleries, he made a fast start, hitting an exquisite approach to six feet at the tricky par-four opening hole and coolly sinking the putt to get to five under. The 14-times major winner struck another pinpoint approach to similar range at the par-four second but his birdie attempt surprisingly horseshoed out of the cup. Woods made his first mistake of the day at the par-four fourth, finding a fairway bunker off the tee and missing a 10-foot par putt to slip back to four under. However he birdied the par-five sixth, where he narrowly missed an eagle putt from 10 feet, and the par-three seventh to reach the turn in two-under 32, five strokes off the lead. Though Woods birdied the par-five 12th after laying up in two and hitting his third shot to within two feet of the cup, he bogeyed the par-four 16th to slide back to six under. Two more pars followed as he failed to make up any further ground on the leaders. Woods now has two rounds left, both at Pebble Beach, as he seeks a first victory on the PGA Tour since the 2009 BMW Championship.