Phil Mickelson well-placed to secure fourth back-to-back PGA Tour title of his career in California The left-hander set the pace on day one with a five-under 66 and, although he could not reach such heights on day two, he did card a one-under 70 to remain at the head of the pack. Mickelson's closest rival for the title, which would follow on from his win at Pebble Beach last weekend, is Pat Perez, who shot the best round of the day with a 65 to reach the halfway stage on five-under, one stroke behind. "I salvaged a good round today," said Mickelson. I've got to go out and shoot some low scores because they're out there, but I gave myself a good opportunity, which is what's so fun about competing and playing the tour - those opportunities at the weekend. Five men occupy third spot going into the penultimate round, with Jimmy Walker, Matt Kuchar, Carl Petterson, Jarrod Lyle and Jonathan Byrd all in with a shout, while Bubba Watson is one of a trio a shot further back on three under. Perez, meanwhile, was not too pleased with his showing, having hit just five of 18 fairways despite his impressive tally. "I didn't hit it like you'd think I would," Perez said. I didn't drive it all that great. I just scrambled well. I put myself in the right places to make par or birdie. A second one-under round of the tournament leaves Briton Justin Rose looking at the lead from just four shots away, while compatriot Luke Donald is five behind. With eight players on the course when darkness fell, the cut has not been entirely confirmed, although Spaniard Sergio Garcia is expected to make it despite crashing to a five-over 76, as is Ireland's Padraig Harrington - one shot better off at two over. American Ryder Cup hopeful Anthony Kim will definitely be heading home early. At 13 over for the championship he was never likely to be in with a chance, but after signing his scorecard incorrectly he was removed from the tournament.