Monday 1 February 2016 18:40, UK
Jason Day, Rickie Fowler and Phil Mickelson were the big-name casualties at the halfway stage of the Farmers Insurance Open as Gary Woodland and KJ Choi shared the lead at Torrey Pines.
Justin Rose also failed to qualify for the weekend on his first start for seven weeks, while Paul Casey also missed the cut by a single shot.
Defending champion Day had been laid low by a flu virus earlier in the week, and admitted he was short on energy after labouring to a two-over 74 which featured three bogeys and a lone, consolation birdie at the last hole.
"You can't live and die by one week," the world No 2 said after finishing at two over. "It's not going to be the last cut I'm going to miss. Hopefully, it is the last cut I'm going to miss this year, but once again it's a process. I've got to keep working hard and hopefully that delayed gratification is a lot more sweeter at the end of the year than it is right now."
Fowler also looked fatigued after arriving in San Diego on the back of his superb victory in Abu Dhabi last week, and the world No 4 was on course to scrape into the weekend until he bogeyed the 17th on the tougher South Course.
The American almost holed his greenside bunker escape at the closing hole, and he had to settle for a par and a round of 71 which left him one outside the cut mark on level par.
Local-favourite Mickelson was two under for the tournament with three to play on the North Course despite a double-bogey seven at the 18th - his ninth - when a wild second shot ended up underneath an out-of-bounds fence next to a car park.
The veteran left-hander clawed both shots back with birdies at the first and second, but he dropped another shot at the fourth and then closed with three straight bogeys to return a torrid 76.
"After that good round on Thursday on the South Course, I thought, 'I'm going to go to the North Course and really light it up.' I think I tried to force the issue a little bit," Mickelson said. "When I wasn't under par early, I kind of started to press a little bit. But that stuff happens."
Rose mixed two birdies with three bogeys in a disappointing 73 which was one too many to play the weekend, while Casey struggled on the greens as he also finished on level par after a 71.
At the top of the leaderboard, Woodland posted a five-under 67 on the South Course, where his immense power was a huge asset as he birdied each of the four par-fives.
The American was joined on nine under by Korean veteran Choi, who has not won on the PGA Tour since lifting his eighth title at the Players Championship in 2011.
The 45-year-old carded seven birdies and two bogeys in his 67 on the North Course, while Dustin Johnson powered to a 66 to claim outright second place on eight under par.
Scotland's Martin Laird is a shot further back after he added a 68 to his opening 69, while Irish star Paul Dunne, making his PGA Tour debut on a sponsor's invite, is just five shots off the lead after rounds of 69 and 71.
