Nathaniel Crosby, the youngest son of the late Bing Crosby, recorded the most onesided victory in today's quarterfinals of the U.S. Amateur golf championship, beating left-hander Bob Michael of Bradenton, Fla., 5 and 4, at the Olympic Club.

Former U.S. Junior champ Willie Wood of Oklahoma State won two matches and gained Saturday's semifinals along with former Los Angeles City titlist Brian Lindley and 1980 U.S. Amateur runner-up Bob Lewis Jr. of Warren, Ohio.

Tony DeLuca of Vienna, Va., lost to Michael on the 20th hole in a second-round match Thursday after upsetting Corey Pavin of Oxnard, Calif., 3 and 1, in the opening round.

Wood had to go three holes in a playoff held late Wednesday and early Thursday to win a place in the match-play field of 64. He took the last available spot.

In today's morning's round, Wood was a hole down with two to play but beat David Lee of Littleton, Colo., 1 up. In the afternoon, he downed Jim Carter of Mesa, Ariz., 3 and 2.

Lewis, a 36-year-old salesman and former pro, won twice by 1-up scores, over Georgia State titlist Bill Bergin and Big 10 champ John Morse of Michigan.

Lindley beat fellow Southern California graduate Brian Gaddy, 3 and 2, and David Tentis of White Bear Lake, Minn., 2 and 1.