Brooks Koepka put in a masterful performance to hold off a final round 63 from Tommy Fleetwood to successfully defend his US Open title at Shinnecock Hills.
Shanghai Masters: Gonzalo Fernandez-Castano Wins by Single Shot
Gonzalo Fernandez-Castano shot a final round of 68 to cap off victory at the Shanghai Masters, his seventh European Tour triumph.
The 32-year-old Spaniard chipped in on 17 to lead the pack by three shots at Lake Malaren, but then a double bogey at the final hole saw him finish only one clear of Francesco Molinari and Thongchai Jaidee.
Italian Molinari held the lead on 10 under, but six birdies in 12 holes gave Fernandez-Castano victory, while elsewhere Paul Casey finished four shots back with Rory McIlroy 10 shots adrift.
American Guthrie, who had looked strong early on, finished fourth, while any hopes of a challenge from Paul Casey disappeared with two bogeys on 12 and 13.
Rory McIlroy was once more plagued by trouble, picking up five bogeys as he finished one over on the day.
Last year's winner Peter Hanson earned the best score of the day with a nine under 63, but a brilliant run of five birdies and an eagle from Molinari set the clubhouse lead at 10-under-par.
The win moves the two-time Italian Open winner up to fourth place in the race to Dubai standings for next month's World Tour Championship.
"On the last I tried to play too conservative and it was a fighting double-bogey that's for sure," said Fernandez-Castano.
He added: "The win comes from some good hard work in Valderrama with my coaches last week and it has paid off."