Tiger Woods and Phil Mickelson advanced to the third round of the World Matchplay Championship amid pouring rain on Thursday.
Woods, the world number one, easily dispatched South Korea's K.J. Choi five and three, while Mickelson, the world number three, beat Brad Faxon, three and two.
Britain's Darren Clarke reached the final 16 by defeating Davis Love III seven and six while Peter Lonard of Australia also advanced with an impressive five and four win over New Zealand's Phil Tataurangi.
They will be joined by defending champion Kevin Sutherland, who beat 23-year-old Briton Justin Rose one-up.
Woods, who has yet to make a bogey in two matches, started his second round match just as he did his first, losing the first hole. He squared the match on the second before eventually taking the lead on the fourth.
"It was just a day of patience out there," Woods said. "You had to go ahead and deal with the conditions the way they are and accept them, and above all keep the ball in play."
The course was severely affected by a heavy downpour of rain, which resulted in the grounds crew having to remove water from the greens so that play could continue.
Woods' adjustments to the conditions included using longer irons then normal to control the spin and keep the ball on a lower ball flight.
"I had a couple of holes where I had 150, 155 and I hit five-irons," Woods said of distance that he would have normally negotiated with a nine-iron.
"You've got to take off the spin or it's going to come ripping off the green."
PATCHY FORM
Mickelson advanced over Faxon in a match in which both players were under par on the front nine, but lost their games on the back nine when neither made a birdie.
"We were even and he made a couple of mistakes, missed a couple of putts you don't see Brad Faxon miss very often," Mickelson said. "That gave me a chance to take the lead."
Of the players left, only Clarke and Sutherland have won this championship. Clarke upset Woods in 2000, while Sutherland beat Scott McCarron last year.
Neither player had a particularly good season last year, with Clarke playing his worst golf since 1994 and Sutherland fading badly after winning at Carlsbad.
"It's nice after the very, very mediocre year I had last year," Clarke said. "It's nice to make the changes I have made and play pretty solid so far this year."
Clarke faces Jim Furyk in the third round.
Sutherland, who defeated Spain's Sergio Garcia in the first round, had the opportunity to win the match against Rose on the 17th hole but missed his short birdie putt.
He then hooked his drive on the par-five 18th into the first fairway where he was blocked by trees from reaching the 18th fairway, so proceeded the play down the first.
"I was thinking I had a fairly easy birdie putt on 17 to close out the match," Sutherland said. "I'm not sure I got that out of my head.
"I was thinking I probably shouldn't be here right now and I hit a horrible shot. I was lucky it didn't go in the water. The only play I had was down the other fairway."
Sutherland gathered himself and made two good shots to reach the green in three and after Rose missed his birdie opportunity, the Briton conceded when Sutherland's first putt nestled close to the hole.
Sutherland meets Australia's Adam Scott in the next round.