Shanghai - Former US Open champion Graeme McDowell gave himself a two-shot cushion ahead of the field after the first round of the WGC-HSBC Champions on Thursday.
Starting on the 10th, the Northern Irishman scorched through his first 12 holes in seven-under par.
Despite two bogeys coming in "G-Mac" was pleased with his opening five-under par 67 at Sheshan which put him two shots clear of six players tied for second on three-under.
"A big key to this golf course is driving the ball well," McDowell told reporters afterwards. "I drove it very well today. I think I missed only one fairway, which is very important. Set up a few opportunities. The greens are in fantastic shape and I putted very well.
"So seven-under par through 12 holes was a beautiful start. Dropped a couple coming in, but all in all, very pleased with five-under par on what I thought was a reasonably tricky day."
McDowell, the 2010 US Open champion, lies 16th on the European Tour's Race to Dubai and needs a high finish in the $8.5 million event here to achieve his goal of getting a shot at a $5 million bonus pool for the top 15 players after the season-ending DP World Tour Championship in a fortnight's time.
The wind switched Thursday and blew harder than on the practice days. With narrow fairways and lush, punishing rough after nearly a week of rain in the city, it all meant that only seven players broke 70 on the par-72, 7,261-yard Sheshan International Golf Club layout.
"This is as tough off the tee as I think I've ever seen this golf course," McDowell added. "If we get three more days of this, I don't think sort of 10-under, 12-under par is going to get beat out there."
One of the sextet in second on three-under par 69 is this year's US Open champion Martin Kaymer.
"I think it's a very good score," said the German world number 13. "So even when I was at one point level par today, but just kept telling myself you will have plenty of birdie chances, so you just need to be patient."
Joining Kaymer on three-under are Americans Rickie Fowler, Brandt Snedeker and Chris Kirk, plus England's Tommy Fleetwood and South Africa's Tim Clark.
"The rough is very rough," said Fowler, who finished in the top five of every major championship in 2014. "I drove the ball well today and hit a lot of fairways. I think I only missed two. That made things a lot easier for me out there. I was able to stay in the short grass today."
Eleven players are a shot further adrift after carding two-under par rounds of 70.
They include world number two Adam Scott of Australia, and the England pair of former world number one Lee Westwood and Ian Poulter, who won this tournament two years ago when it played at Mission Hills in Shenzhen.Leading scores Thursday after the first round of the $8.5 million
World Golf Championships-HSBC Champions at Sheshan International Golf
Club, Shanghai (par 72):
67 - Graeme McDowell (NIR)
69 - Rickie Fowler (USA), Brandt Snedeker (USA), Chris Kirk (USA), Tim Clark (RSA), Tommy Fleetwood (ENG), Martin Kaymer (GER)
- Dawie van der Walt (RSA), Louis Oosthuizen (RSA), Kim Hyung-Sung
(KOR), J B Holmes (USA), Jaco van Zyl (RSA), Lee Westwood (ENG), Ian
Poulter (ENG), Adam Scott (AUS), Henrik Stenson (SWE), Bill Haas (USA),
Jordan Spieth (USA)
71 - Thongchai Jaidee (THA), Jamie Donaldson
(WAL), Kevin Na (USA), Russell Henley (USA), Brendon Todd (USA), Oliver
Wilson (ENG), Patrick Reed (USA), Bubba Watson (USA), Jonas Blixt (SWE)
- Marcel Siem (GER), Thorbjorn Olesen (DEN), Marc Leishman (AUS),
Keegan Bradley (USA), Stephen Gallacher (SCO), Justin Rose (ENG), Thomas
Bjorn (DEN), George Coetzee (RSA), Jason Dufner (USA)