CHERRY HILLS VILLAGE, Colo. (AP) -- Steven Fox took advantage of a strong start to beat Chris Williams, the world's top-ranked amateur, in the quarterfinals of the U.S. Amateur championship at the Cherry Hills Country Club on Friday.
Fox, 21, of Hendersonville, Tenn., defeated the 21-year-old Williams, of Moscow, Idaho, 4 and 2. A senior at the University of Tennessee-Chattanooga, Fox will play Brandon Hagy, 21, of Westlake Village, Calif., in a semifinal Saturday. Hagy, one of two golfers from the University of California to reach the semifinals, defeated Cheng-Tsung Pan, 20, of Taiwan 4 and 3.
Michael Weaver of Fresno, Calif., who is also a member of Cal's golf team, advanced by defeating Ricardo Gouveia of Portugal 4 and 3. He'll meet Alabama's Justin Thomas of Goshen, Ky., in the other semifinal. Thomas edged Australian Oliver Goss 2 up to secure his semifinal spot.
Fox made two birdies with no bogeys on the front nine. Williams had two bogeys.
"This is by far the best thing I've done in my career, by far," Fox said.
"I knew I had to play well and had to bring my 'A' game, and luckily I did," said Fox, who advanced to match play after winning a playoff in qualifying earlier this week. "But we started out and I got 2-up through four, and to be 4-up after nine was beyond expectations. I thought it was going to be a really close match. I give him respect for being the No. 1 amateur, but luckily I got it done."
Like Fox, Weaver parlayed a strong start into a victory over Gouveia, who hadn't trailed in any of his matches before the quarterfinals.
Weaver was up by two holes after five and stretched his advantage to 4-up after nine.
He failed to advance to match play in last year's amateur when he missed the cut by a stroke and had to survive a playoff just to get into match play at this year's event.
"I'm having a great week. Couldn't be happier," Weaver said. "Just to make it through the playoff was great. I feel like I've played smart and I've put myself in a great position."
Thomas, 19, who won the Jack Nicklaus award as the nation's top collegiate golfer, was only 1-up on Goss heading into No. 18. Thomas was able to make par and the 18-year-old Goss, an incoming freshman at Tennessee, missed a long putt from the lip of the green to try to square the match.
"It was a hard match," Thomas said. "You're obviously not going to get any easy matches at this point. It feels great to be moving on and I'm very, very honored."
Hagy birdied the seventh hole to take his first lead. He stretched his lead to 2-up when Pan, who plays for Washington, bogeyed No. 10.
"I think that stretch right there ... was huge," Hagy said. "Then I birdied the next hole to go 1-up. That was a huge swing. I played really consistent the whole rest of the way."