Ernie Els established a three up lead over Luke Donald at the turn as the South African made a good start to their last 16 clash at the World Golf Championships - Accenture Match Play.
Els hit a scintillating five iron approach shot 240 yards to leave a ten foot eagle putt at the eighth although the Englishman recovered to take a half before Els won the next hole to reach the turn three up.
Stewart Cink and Phil Mickelson were involved in an intriguing all American match and it was Cink - who saw off the challenge of Lee Westwood at the 23rd hole in the second round - who made a lightning start.
The Ryder Cup player reached three up after six holes but Mickelson fought back strongly to reduce the deficit to one after eight before Cink won the ninth to go two up at the turn.
Ross Fisher continued his outstanding form from the second round to lead by three after seven holes against veteran Jim Furyk.
Fisher beat Pat Perez 6 and 5 in the second round and the Englishman recorded a series of early birdies to dominate his American opponant.
Justin Leonard and Oliver Fisher looked set for another tight battle, the duo deadlocked at all square after six holes.
Tim Clark, buoyed by his victory over Tiger Woods, was overshadowed early on by Northern Irish teenager Rory McIlroy who came through in a tight encounter against Hunter Mahan to reach the last 16.
McIlroy stormed out of the blocks - chipping to within a few feet to win the first before advancing to three up after five holes.
His tee shot at the par three sixth hole bounced down the slope below the flag to leave a makeable ten foot putt, which he holed to go four up.
Geoff Ogilvy came back after an early set-back against Camilo Villegas, the Colombian, who has been in excellent form in his opening two matches.
Villegas made the first move but Ogilvy turned it around to be one up after five holes.
Ian Poulter and Sean O’Hair are contesting the third England versus America match up and the Englishman made two confident six foot putts in the first two holes to go two up.
Peter Hanson goes against Paul Casey in the final contest for a place in the quarter-finals. A quick start from Casey saw him win the first two holes of his tie, a 25 foot putt on the second right into the back of the hole leaving him two up.
