Russell Knox set the clubhouse target on day two of the World Golf Championships - HSBC Champions as a 65 catapulted him to the top of the leaderboard.
The Scot was a late entry at Sheshan International Golf Club having initially been seventh reserve but he made the most of his opportunity to get to 12 under and hold a share of the lead with American Kevin Kisner.
Kisner had begun the day a shot behind overnight leader Branden Grace but he picked up four birdies in his first eight holes and was also 12 under with three to play.
Grace had got to that mark after picking up three shots in his opening ten holes but two bogeys on the back nine dropped him back to ten under with a 71.
Knox carded an opening 67 to lie four shots off the lead but after starting his second round on the back nine, the 30 year old picked up shots on the tenth, 13th and 18th to reach the turn in 33. Further birdies on the second, third, fifth and eighth then saw him come back in 32 in an unblemished effort.
Kisner had picked up birdies on the second, sixth and seventh and, when he also birdied the eighth, a bogey from Grace on the 11th saw him move into the lead before seven straight pars followed.
Grace opened with four pars but picked up a shot on the fifth for the second day in a row before a nice approach to the par five eighth left him five feet for his second birdie of the day.
Another followed on the tenth but the shot was dropped on the 11th and, after scrambling an impressive par on the 14th, a second dropped shot of the day, and indeed the week, came on the 15th.
Li Haotong and Patrick Reed were then at nine under after contrasting finishes to their rounds.
The local favourite turned in 34 and further birdies on the third and fifth got him into double figures before a disappointing bogey on the ninth.
Reed had also got off to a good start with back-to-back birdies on the fifth and sixth but he dropped shots on the eighth and 15th before two birdies in three holes got him to nine under.
Three consecutive birdies from the 14th helped Bernd Wiesberger to a 66 and eight under, a shot clear of Scott Hend, who signed for a 69, and Steven Bowditch, Dustin Johnson and Louis Oosthuizen who were still out on course.
There was then a large group at six under led by Ross Fisher, Tommy Fleetwood, Sergio Garcia and Thorbjørn Olesen who were all in the clubhouse.
Danny Willett was also six under with four to play as he attempts to chase down Race to Dubai leader Rory McIlroy who endured an inconsistent day.
The World Number Three had four bogeys and four birdies through 17 holes to sit four under while World Number Two Jordan Spieth was two shots further back after three consecutive bogeys from the 11th.
