Richie Ramsay became Britain's first US Amateur champion in 95 years with a 4&2 win over American John Kelly at Hazeltine National on Sunday.
Ramsay will partner Phil Mickelson in the first two rounds at Augusta
The 23-year-old Scot, who played in last year's Walker Cup, sealed victory in the 36-hole final with a birdie at the par-four 16th.
The Stirling University student had led by two after the morning round.
"There's been a lot of up and downs, and I just can't believe I'm here at the moment," said Ramsay.
"I played according to the game plan and sometimes it didn't come off. We just were going out there having a bit of fun.
"We played the course and I've been swinging it good all week.
"A lot of it is all mental out there and my mental game was first class this week. I've worked hard on it and managed it well this week."
Ramsay now receives exemptions into next year's Open, Masters and US Open if he maintains his amateur status.
The Aberdeen star will partner defending champion Phil Mickelson in the first two rounds of the Masters at Augusta next April.
Ramsay, the first Briton to reach the final since Jack McLean in 1936, became the first British winner of the prestigious event since Harold Hilton in 1911.
Italy's Edoardo Molinari became the first European champion since Hilton by winning in 2005.
Other names on the Havemeyer Cup include Arnold Palmer, Jack Nicklaus, Phil Mickelson and Tiger Woods.