Jordan Spieth knocked off defending champion Matt Kuchar, 2 and 1, in the third round of the WGC-Accenture Match Play Championship at the Golf Club at Dove Mountain in Marana, Ariz.
The 20-year-old Spieth, youngest player in the field, held a 3-up lead after 10 holes before giving the next two holes to Kuchar with bogeys, but wrapped up the match with an 11-foot birdie putt on the 17th hole.
Kuchar had won his last eight matches and 11 of the last 12 in the Accenture.
“I was struggling right there,” said Spieth, whose only PGA Tour victory came in the 2013 John Deere Classic. “I hit in out (of bounds) on 11 and plugged in a bunker at 12 to give him two holes to get back in it.
“But I saved myself around the green with my wedge to save some pars before making that last birdie (his ninth of the day). I’m excited to be in the quarterfinals.”
Spieth will play Ernie Els of South Africa, who made a three-foot birdie putt on the last hole to turn back PGA champion Jason Dufner, 1 up.
Rickie Fowler birdied two of his last three holes, including a four-footer on the 18th to claim a 1-up victory over Sergio Garcia of Spain, who conceded a 17-foot birdie putt to Fowler on No. 7 because he guilty for taking so took long to take a drop one hole earlier.
Fowler will play Jim Furyk, who chipped from 30 feet in for birdie on the 16th hole to take the lead from Harris English and halved the next two holes for a 1-up victory.
Graeme McDowell of Northern Ireland trailed for much of the day, but pulled even with 2012 Accenture champion Hunter Mahan with a five-foot birdie putt on the 18th hole. Then he holed two putts of about 20 feet, the first for par to stay alive on the second extra hole and the second on the 21st hole to win it.
In the quarterfinals, G-Mac will play surprising Victor Dubuisson of France, who built a 3-up lead over Bubba Watson and held on for a 1-up victory.
Also advancing were Louis Oosthuizen of South Africa, with a 5-and-4 victory over Webb Simpson, and Jason Day of Australia, with a 2-and-1 victory over George Coetzee of South Africa. Oosthuizen and Day will meet in the quarterfinals.
