Graeme McDowell made a third comeback in as many days to book a quarter-final place in the WGC Accenture World Match play.
McDowell had come from behind to beat Gary Woodland and Hideki Matsuyama and it looked like he was on his way out again when falling two behind to Hunter Mahan with a bogey at the 16th.
But he won the next with a par before a superb birdie sent the match against his former Ryder Cup foe into extra holes.
His putter got him out of trouble again to stay alive before a fine birdie at the 21st sent Mahan on his way.
McDowell will play in-form Frenchman Victor Dubiusson for a place in the semi-final after he fought off a late rally from Bubba Watson to win on the 18th.
Former Open champion Louis Oosthuizen followed an easy victory over top seed Henrik Stenson by defeating Webb Simpson 5&4.
Oosthuizen was six under par for the 14 holes completed thanks to an eagle and four birdies and said: "I played really solid. The only hole I looked like making bogey was the 10th and I made an 18-20 footer for par.
"I'm putting really well and my ball-striking is improving every day and I am just trying to give myself as many birdie chances as I can."
Oosthuizen faces Jason Day in the last eight after the Australian defeated George Coetzee 3&1.
Jim Furyk came from three down after six holes to beat rising star Harris English, who had beaten Lee Westwood and Rory McIlroy in the first two rounds, one-up.
Furyk, who had never reached the last eight before in 13 previous attempts and has been two down or worse in each of his three matches, will face compatriot Rickie Fowler after he birdied the 18th to edge past Sergio Garcia, who was involved in a bizarre incident when he offered Fowler a half despite the American facing a putt of around 20 feet.