(CNN) -- World No. 1 Lee Westwood's miserable record at the World Match Play continued as more top names crashed out of the $8.5 million tournament in Arizona.
The Englishman lost to American Nick Watney for the second year in a row as he followed fourth-ranked Phil Mickelson, two-time runner-up Paul Casey, former world No. 1 Ernie Els and rising star Rory McIlroy in making a second-round exit.
Many of the tournament's top names have now departed, with three-time winner Tiger Woods and defending champion Ian Poulter losing in Wednesday's opening round at Dove Mountain's Ritz-Carlton course.
The 37-year-old Westwood, who has never made it past the second round, struggled with his putting as he lost 1-up to Watney after halving his deficit with a birdie at the 14th hole before parring his last four.
"I putted very poorly all day long. The game's in good shape, but I have just not worked hard on my putting and it showed," Westwood told reporters.
Watney, who lost in the third round last year, will now face Ryan Moore on Friday after his fellow American beat Korean veteran K.J. Choi 5 & 4 in the Bobby Jones quarter of the 64-man field.
The winner of that last-16 match will play either Italian teen Matteo Manassero or Englishman Luke Donald in the quarterfinals.
Manassero, the youngest player to ever line up in a World Golf Championship event, continued his dream debut with a 1-up victory over South African Charl Schwartzel.
The 17-year-old birdied the 17th hole and then parred the next along with his opponent to set up a clash with world No. 9 Donald.
Donald beat his Ryder Cup teammate and Manassero's compatriot Edoardo Molinari 2 & 1 with a birdie at 17 in a match in which he never trailed but never led by more than two.
Four-time major winner Mickelson, seeded top in the 16-man Ben Hogan bracket, was thrashed 6 & 5 by young compatriot Rickie Fowler in the second round.
Fowler, the 2010 PGA Tour rookie of the year, will next face Matt Kuchar -- who beat their fellow American Bo van Pelt 3 & 2 to reach the last 16.
The winner of that match will face either U.S. Open champion Graeme McDowell or 2009 PGA Championship winner Y.E. Yang in the quarterfinals.
Northern Irishman McDowell beat European Ryder Cup teammate Ross Fisher of England 4 & 2, while Korean veteran Yang won 4 & 3 against Poulter's American conqueror Stewart Cink.
World No. 6 Casey lost 4 & 2 to Australia's Jason Day in the Sam Snead group.
The 23-year-old, who last year became the youngest golfer from his country to win on the PGA Tour, earned a clash with J.B. Holmes after the American eliminated Els 1-up in a seesaw match.
The South African went behind for the fifth time at the 16th hole and could not peg back Holmes again as the duo parred the final two holes.
Bubba Watson thrashed fellow American Mark Wilson 6 & 5 to set up a last-16 clash with Australia's two-time champion Geoff Ogilvy.
Ogilvy, the winner in 2006 and 2009, beat Woods' Danish conqueror Thomas Bjorn on the final hole.
Bjorn squared a tight match with par at 17 as his opponent bogeyed, but a reversal of that at 18 saw Ogilvy go through.
World No. 7 McIlroy, who made the quarterfinals here as a 19-year-old in 2009, suffered an embarrassing 8 & 7 thumping by American Ben Crane in the Gary Player section.
The Northern Irishman, who comfortably beat Crane's compatriot Jonathan Byrd on Wednesday, did not win a single hole as he had to concede after the 11th.
"I just got going early on and felt comfortable and Rory didn't have his best day," the 34-year-old Crane told reporters after inflicting one of the biggest defeats in the tournament's history.
"I got off to a great start and parred one, and then the holes opened up."
Crane will next play Miguel Angel Jimenez, the oldest player in the 64-man field, after the 47-year-old Spaniard won 4 & 2 against American Ryan Palmer.
Palmer, a three-time PGA Tour winner, went ahead at the first hole but it was all downhill from there for the 34-year-old until a brief respite at 14.
U.S. Ryder Cup player Hunter Mahan progressed after winning the last three holes of his match against Sweden's Robert Karlsson, beating the former European Tour No. 1 2-up.
Mahan will next play world No. 2 Martin Kaymer after the German defeated England's Justin Rose on the 20th hole in the final match to be completed -- the only one that went beyond regulation play.
