A tie for eighth in March’s Arnold Palmer Invitational, part of The Open Qualifying Series, was good enough to earn Riley the third and last qualifying spot.
Joint runner-up Rory McIlroy and fourth-placed quartet Scottie Scheffler, Tyrell Hatton, Jordan Spieth and Patrick Cantlay were already exempt, while Trey Mullinax was alongside Riley on six under par, but had the lower world ranking of the pair.
It will be the 26-year-old’s debut and he said: “The Open is one of those championships you dream of playing as a kid. You watch the greats like Arnold Palmer, Jack Nicklaus, Gary Player - the names are endless -so it’s great to finally have this come to fruition. I played the Junior Ryder Cup at Blairgowrie (in 2014) although the course wasn’t true links. I can’t wait to get my first taste of it at Royal Liverpool."
Twice made the final of the US Junior Amateur, something previously achieved only by Tiger Woods and Spieth. The two players who beat him were Will Zalatoris and Scheffler, who won on the final hole in 2013 after Riley called a penalty on himself.
Two years later he was ranked the best college player in the States. Played the 2015 US Open as an amateur and on his first appearance at the PGA Championship last year tied for 13th only five strokes behind winner Justin Thomas.