Russell Knox starts well in defence of WGC Champions title in Shanghai
|WGC-HSBC Champions first round|
|-8 R Karlberg (Swe), -7 R Fowler (USA), -6 R Knox (Sco), D Berger (USA), H Matsuyama (Jap)|
|Selected others: -5 P Casey (Eng), -4 S Garcia (Esp), -3 H Stenson (Swe), A Scott (Aus), -1 R McIlroy (NI) +2 D Willett (Eng)|
Scotland's Russell Knox made a strong start to the defence of his WGC-HSBC Champions title in Shanghai.
The 31-year-old shot a bogey-free 66 at Sheshan International to finish six under par, two shots behind Sweden's Rikard Karlberg.
American Ryder Cup star Rickie Fowler, playing with Knox, shot a 65 to sit second after the first round.
Knox aims to become only the second player after Tiger Woods to retain a World Golf Championships title.
After starting on the back nine, Knox followed four straight pars with the same number of birdies in succession from the 14th, before picking up further shots on the third and seventh.
"I'm always thrilled with no bogeys and my first round is never my strongest round," said the world number 20 from Inverness.
"I didn't put any pressure on myself. I didn't feel overly tight out there, so I was proud of myself to kind of relax and enjoy it. It can only be your first defence once, so I'll make sure I'm going to have a good time the next three days.
"The conditions were just like this on Sunday last year, very dark and dreich, as the Scots would say, with a little mist and rain. The course played long today, which is fine for me.
"If it's lift, clean and place [preferred lies], as long as I'm on the fairway I can compete around here."
Knox was joined on six under par by American Daniel Berger and Japan's Hideki Matsuyama, with England's Paul Casey on five under, along with Francesco Molinari, another former champion, and Bill Haas.
Spain's Sergio Garcia is a shot further back, while Rory McIlroy ended the day seven shots off the pace after a round of 71.
Surprise leader Karlberg birdied his first four holes and reached nine under par after 16, only to bogey the 18th after finding sand off the tee and thick rough with his recovery.
"Everything was so easy," he said. "It was just one of those days, it was a walk in the park. I committed to a lot of shots, hit them perfect, just as I wanted and I stayed aggressive on my putting all the way around, which I feel was good.
"I hit great shots all day except the last hole and it was a great day. It felt amazing on every part of the game."