SYDNEY: Young American Jordan Spieth dominated the final round to win the Australian Open by six shots and leave world number one Rory McIlroy and third-ranked Adam Scott in his wake on Sunday.
Spieth carded a sizzling new course record of eight-under 63 to finish the Aus$1.25 million (US$1.06 million) OneAsia co-sanctioned tournament at 13-under 271.
It was 21-year-old Texan’s second career tournament win and his first since last year’s triumph at the John Deere Classic in Illinois.
Spieth was runner-up at the Masters last April behind fellow American Bubba Watson, just missing out on being the first Masters rookie to win since Fuzzy Zoeller in 1979.
Spieth took a grip on the final round with three consecutive birdies from the fifth to the seventh holes to go nine under and led overnight co-leader Brett Rumford by three at the turn.
He had few problems holding on to his advantage in the homeward nine with four more birdies in his closing five holes to post his best tournament victory.
With his comprehensive victory, Spieth’s world ranking is expected to climb from 14 to 11.
Australian Rod Pampling finished second at seven-under 277 with Brett Rumford third on six-under 278 and Greg Chalmers in fourth on five-under 279.
Scott lost momentum with a double-bogey seven at the fifth hole to drop back to two under and could make little headway on the tearaway leader to finish fifth with four-under 280.
The world No.3 had to take a penalty drop for an unplayable lie after blocking his tee shot into rough and then hooked his next shot back into the trees on the left.
He speared through a narrow opening but was unable to get up and down, the double-bogey leaving Scott five behind Spieth at that stage.
Defending champion McIlroy, who beat Scott with a birdie at the final hole at Royal Sydney last year, struggled with the course and the windy conditions and failed to make a final round charge, finishing joint 15th, some 15 strokes behind Spieth.
The Northern Irishman had a total of 15 birdies, an eagle, 14 bogeys, one double bogey and a disastrous triple bogey this week at the Open.
Only eight players finished under par over the 72 holes at the demanding Jack-Nicklaus designed course.
Spieth joins past winners of the Stonehaven Cup such as greats Jack Nicklaus, Gary Player, Greg Norman, Tom Watson and Peter Thomson.
He is the first American since Brad Faxon in 1993 to win the Australian Open.
Last year Spieth won the John Deere Classic at age 19, becoming the first teen winner of a US PGA Tour event since 1931.
Spieth also became the youngest player to win two Ryder Cup matches at the age of 21 years and 62 days at Scotland’s Gleneagles in September.
Rumford, Pampling and two-time winner Chalmers qualified for next year’s British Open as the top three non-exempt players.