Hideki Matsuyama took a three-shot lead on day two of the World Golf Championships - HSBC Champions, while Rory McIlroy surged up the leaderboard.
Matsuyama began day two in Shanghai two strokes behind overnight leader Rikard Karlberg but raced clear with a seven-under 65.
The Japanese started and finished the front nine with bogeys, though a quartet of birdies enabled him to reach the turn at 34.
Matsuyama gained a further five shots on the back nine, meaning he is yet to shoot a round of 70 or over in the 2016-17 season.
Hideki's first 6 rounds of the 2016-17 season ...-- PGA TOUR (@PGATOUR) October 28, 2016
He leads by 3 at the season's first WGC. pic.twitter.com/YQ5NfaINOK
Defending champion Russell Knox was unable to keep pace with Matsuyama, but a four-under 68 sent him up to second alongside Bill Haas, the American carding his second 67 of the competition.
After a disappointing 71 on Thursday, FedEx Cup winner McIlroy put in a vastly improved second round that included seven birdies - a bogey at the 16th stopping him from joining Francesco Molinari, Richard Bland and Daniel Berger in fourth.
Instead, the Northern Irishman sits seventh with Ross Fisher, Zhang Xinjun and Paul Casey.
Karlberg paid the price for five bogeys on the front nine as he slipped down to tied-13th, while Patrick Reed's luck failed to turn.
The American's approach shot on the eighth clipped the pin and spinning away into the water to keep him close to the foot of the leaderboard.
Sergio Garcia, Martin Kaymer, Alex Noren and last year's Open Championship winner Henrik Stenson are nine shots off the pace, while Dustin Johnson, the 2013 winner of this event, Adam Scott and Danny Willett are all over par for the tournament.