Tony Finau held a one-shot lead heading into the final nine holes as the WGC-HSBC Champions looked to be developing into a three-horse race at Sheshan International Golf Club.
The American entered the day with a three-shot lead but turned in level par to stay at 13 under and see his advantage trimmed by countryman Xander Schauffele, with defending champion Justin Rose a further shot back.
Masters Tournament champion Patrick Reed was the next closest challenger at eight under having turned in 38.
Finau and Schauffele are both looking for maiden wins on the European Tour while a win for Englishman Rose would see him move back to the top of the Official World Golf Ranking.
Finau missed from inside five feet on the first to see his lead cut to two but recovered beautifully, getting on the green at the par five second in two to make a birdie.
Schauffele and Rose both found sand with their second shots on the same hole but played excellent bunker shots for birdies of their own to stay two back.
Rose needed to hole an eight-footer for par on the third and the leading trio all found bunkers with their tee-shots on the par three fourth, with Schauffele failing to get up and down.
The 25 year old bounced straight back with a 16-foot right-to-lefter on the next but it was Rose who cut the lead to one, holing a ten-foot putt on the seventh.
The eighth brought drama as Finau put his second in the hazard but hit an exquisite fourth to tap-in range to heap pressure on Rose who faced a slippery 12-footer to save par after hitting a poor tee-shot. He made it to stay at 12 under where he was joined by Schauffele, who played the par five in more routine fashion for a birdie.
Rose could not repeat his heroics at the next after finding the cart path off the tee and he was two behind at the turn.
American Reed made bogeys on the fourth and sixth to sit a shot ahead of countryman Andrew Putnam, Thai Kiradech Aphibarnrat and England's Tommy Fleetwood.
Belgian Thomas Pieters made the first ever hole-in-one at the 12th hole at Sheshan as his six iron off the tee from 197 yards took two bounces and rolled into the cup.
