Shanghai, China: Justin Rose will have one more day to try to catch leader Tony Finau after the American fought off a challenge from the defending champion in the third round of the WGC-HSBC Champions tournament.
Finau ground out a hard-fought two-under 70 to end Saturday at 13 under par overall, three strokes ahead of playing partners Rose and Masters champion Patrick Reed, who also each carded a 70.
Joining Reed and Rose at 10-under was American Xander Schauffele, who posted a 69.
Finau, the overnight front-runner, surrendered the leaderboard to Rose with a shaky front nine at Shanghai's Sheshan International Golf Club.
But he capitalised on the Englishman's own mistakes down the stretch to stay on track for just his second PGA Tour win.
Teeing off with a three-stroke lead over Rose and Reed, Finau faltered with a pair of early bogeys and couldn't get back to par for most of his round, as four birdies on the front nine put Rose in front.
But Rose lost his grip with a costly double bogey on the par-3 17th, followed by a bogey on 18, just as Finau rattled off three closing birdies to once again take a three-stroke advantage into the final round.
Finau, of Samoan and Tongan descent, is the first player of that ancestry on the PGA Tour and the first Polynesian to play in the Ryder Cup, where he provided a rare bright spot as a USA captain's pick in last month's crushing loss to Europe.
His only PGA win so far was the 2016 Puerto Rico Open.
But his star has risen, with 11 top-10 finishes in 2018, including at three majors, and his Ryder Cup performance.
Finau is currently ranked world number 17.
The tournament, dubbed "Asia's major", annually gathers a premier field with its winner's purse of $1.8 million.