Rose is ranked 40 places behind Mickelson

Rose outplayed his illustrious rival to set up a meeting with Charles Howell III in the last 16.

World number one Tiger Woods made short work of Tim Clark, racing to a 5&4 win.

Paul Casey was also on good form and saw off his Ryder Cup team-mate Colin Montgomerie 4&3 thanks to a surge over the latter holes.

606 DEBATE: Put your questions to Justin Rose's coach

Montgomerie got off to a dreadful start, losing three of the first four holes, but clawed his way back to trail by just one at the 12th.

But Casey reeled off the next three holes to seal a place in the next round.

England's Luke Donald fell at the final hurdle to Aaron Baddeley after the Australian birdied the 18th hole.

Donald was 3up after 12 holes but made two bogeys on the way home to let his opponent make it all square going into the last.

"I was pretty much in control after 12 holes," said Donald.

"Two over for the last six holes is not going to get it done. I only have myself to blame."

Meanwhile, Rose said his superb 35-foot birdie putt at the 15th had been crucial to his victory.

"The key was holing that putt, the first long putt I've made all week," he Rose.

"It was a nip-and-tuck game and I finally got my nose in front coming down the back nine."

Poulter has looked in good form in Arizona

Ian Poulter progressed with a 3&1 win over Welshman Bradley Dredge, while Retief Goosen suffered a surprise one-hole loss to Niclas Fasth.

Poulter, who beat Bart Bryant in the opening round, will now face Trevor Immelman after the South African beat Chris DiMarco 3&1.

He was never behind against Dredge although the Welshman won the 9th and 12th holes to get back to all square, only to lose the next two.

The 31-year-old Poulter said he had set the tone by nicking a half at the par-five first hole.

"I made a cheeky par, rolled in a 20-footer," he said.

"He was probably expecting to go one up. I was over the moon to walk away with a half.

"It was a great game. I think I had six birdies and no bogeys, and that's pretty tricky to play against.

"You know you've only got 18 holes to perform. It's almost like going out in contention on Sunday.

"You've got a nice buzz, the adrenalin going, and generally when I'm in that frame of mind, I perform pretty good."

Ireland's Padraig Harrington fought back from four holes behind against Stewart Cink to give himself a chance, but the American held his nerve at the last to win by one hole.

Geoff Ogilvy beat Spain's Jose Maria Olazabal 2&1 to go through, while Sweden's Henrik Stenson overcame KJ Choi 2up.

Olazabal's fellow Spaniard Sergio Garcia also crashed out of the tournament with a 4&3 defeat by Charles Howell III.

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