Xander Schauffele celebrated his 25th birthday week in some style by beating fellow American Tony Finau in a play-off to win the WGC-HSBC Champions at the Sheshan International course on Sunday.
The 2017 PGA Tour rookie of the year picked up birdies on the last two holes of his final round to join Finau on 14-under-par and sank a birdie putt on his second trip to the 18th green before watching Finau come up short with a longer effort.
Schauffele, who turned 25 on Thursday, mixed six birdies with two bogeys for a fourth round four-under 68 to rein in Finau, who started the day with a three-stroke advantage and finished with a 71.
Defending champion Justin Rose shot a 72 to finish four shots behind the leading pair in third place, which was only just insufficient for the Briton to replace Brooks Koepka as world No 1.
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It was a third victory on the PGA Tour for Schauffele after his wins at the Greenbrier Classic and Tour Championship in 2017 and earned him a cheque for $1.7 million (Dh6.24m) along with a big kickstart in the race to the 2019 Fedex Cup.
"It means a lot, last season I really wanted to justify my rookie year by winning but I wasn't able to do it," the Californian said. "This wasn't the same season but it's the same calendar year so I'll take it."
Thai Kiradech Aphibarnrat shared fourth with American Andrew Putnam at eight-under - an impressive feat for both in an exclusive field featuring all three 2018 major winners as well as five of the top six golfers in the world.
Koepka shot a final round 69 to finish in a share of 16th and retain the No 1 ranking he claimed for the first time after winning the CJ Cup in South Korea last weekend.
Rory McIlroy's hopes of reining in Francesco Molinari at the top of the Race to Dubai standings were not realised as the Northern Irishman finished in a tie for 54th at 10-over-par, three shots behind the Italian.
Schauffele, Finau and Rose played together in the final group and for much of the day it looked almost like a matchplay contest with the trio only separated by two or three strokes.
With high winds and firming greens making low scores difficult, Finau's overnight lead gave him the upper hand heading into the back nine.
Schauffele could have taken the lead as Finau bogeyed the 12th only for his birdie putt to curl around the hole. A huge tee shot at the 13th, however, saw him edge a shot ahead at 13-under.
Finau got back in front with a birdie as Schauffele bogeyed 15th and the two ran neck-and-neck as Rose faltered over the final few holes to drop out of contention.
Schauffele summoned up a brilliant tee shot and an equally good birdie putt at the par-three 17th and could have claimed the prize without a playoff after sending his eagle putt inches past the hole after flirting with the water at the 18th.
"I felt like I was playing great all day ... I felt like I was in control of my ball and kept my head down," Schauffele said.
"When I signed my card I went 'Oh wow, I went birdie-birdie to get into this playoff'. I was in a world of my own out there."