Arizona-based Gaylord Sports Management issued a release at the site of the 132nd British Open. Barnes, a senior at the University of Arizona, had been expected to make the announcement this week.
Barnes won five times in four years at Arizona, was his team's low man in 24 of 55 events, set the school's all-time record in scoring average at 71.48 and is the only Wildcat in history to finish in the top 20 in four NCAA Championships.
Barnes defeated Hunter Mahan in last year's U.S. Amateur final. He will make his pro debut at the International next month in Colorado.