Michigan sophomore Kyle Mueller held off U.S. Amateur stroke-play medalist Brett Coletta of Australia 1 up Wednesday at Olympia Fields in the first round of match play.
Mueller, from Watkinsville, Georgia, survived a playoff Wednesday morning to advance to match play. He took a 3-up lead with a par won on the par-4 11th, lost the par-3 15th and 17th with bogeys and finished off the 19-year-old Coletta with a par for a halve on the par-4 18th.
South Korea's Gunn Yang, the San Diego State player who won last year at Atlanta Athletic Club, dropped out with a 3-and-2 loss to Wake Forest freshman Cameron Young of Scarborough, New York.
NCAA champion Bryson DeChambeau of SMU routed Robby Salomon of Monterey, California, 8 and 6. DeChambeau, from Clovis, California, won Nos. 3 and 5-10 and ended it with a birdie on the par-4 12th.
Arizona State senior Jon Rahm, the Spanish player who tops the world amateur ranking, beat Arizona sophomore George Cunningham of Tucson, Arizona, with a birdie on the 21st hole. Rahm won the first three holes, Cunningham tied it on the 13th and they halved the next seven.
Brad Nurski of St. Joseph, Missouri, had the most-lopsided victory, beating New Zealand's Josh Munn 8 and 7. Nurski won the final seven holes on the front nine and closed out Munn with a birdie on the 11th. The 36-year-old Nurski is a conductor and switchman for Burlington Northern Santa Fe Railway. He finished second in the 2014 U.S. Mid-Amateur.
Todd Mitchell of Bloomington, Illinois, at 37 the oldest player in the match-play field, edged South Florida senior Chase Koepka of West Palm Beach, Florida, 1 up. Mitchell is an insurance agent who spent two seasons as in infielder in the New York Yankees' farm system. Koepka is the brother of PGA Tour player Brooks Koepka.
Alabama junior Robby Shelton of Wilmer, Alabama, beat Washington State freshman Aaron Whalen of Ephrata, Washington, 5 and 3; Florida freshman Sam Horsfield of England advanced with a 6-and-5 victory over Colorado State freshman Jake Staiano of Cherry Hills Village, Colorado; and 17-year-old Ryan Ruffels of Australia beat Texas junior Beau Hossler of Mission Viejo, California, 5 and 4.