Tacoma, United States (AFP) - Jordan Spieth won the US Open at Chambers Bay on Sunday, two months after winning the Masters at Augusta National.
The 21-year-old Texan closed with a 69 for a five-under total of 275, one shot clear of fellow American Dustin Johnson (70) and South African Louis Oosthuizen (67).
Johnson had a four-foot putt at the last to force a 18-hole playoff on Monday but he missed it.
Spieth is the first man since Tiger Woods in 2002 to win the Masters and the US Open in the same year, and the victory takes him halfway to winning all four majors in the same year, a feat no player has ever achieved before.
He is also the youngest champion of the US Open since the legendary Bobby Jones in 1923 and the youngest player to win two career majors since Gene Sarazen in 1922.
Spieth started the day in a share of the lead with four others but fell back with a bogey at the first.
He edged his way back into a share of the lead with Grace going down the back nine and a snaking 27-foot birdie putt at the 16th put him three clear with two to play as the South African hit out of bounds for a double bogey.
He took a double bogey of his own at the 17th but birdied the last to take the lead.
Playing in the final pairing, Johnson reached the par-five green in two and had a 12-foot eagle putt to win his first major title.
That effort slipped agonisingly four feet past and he missed the one back to force the playoff.
Three players were tied for fourth - Australians Adam Scott (64) and Cameron Smith (68) and South African Branden Grace (71).