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 golf course 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 University of Alabama freshman Justin Thomas of Goshen, Ky., in the other semifinal. Thomas edged Australian Oliver Goss 2 up to secure his semifinal spot.

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