Hideki Matsuyama got off to a rough start in his bid to defend the World Golf Championships-HSBC Champions title on Thursday, carding a 2-over-par 74 in the first round.
The world No. 4 made three birdies, two bogeys and a triple bogey at Sheshan International Golf Club and is tied for 67th, trailing leader and U.S. Open champion Brooks Koepka by 10 shots.
Koepka sizzled with a 64 for a one-stroke lead over Gavin Green of Malaysia and Thailand's Kiradech Aphibarnrat.
Matsuyama, who he became the first Japanese to win on the WGC series with an emphatic seven-stroke victory at this tournament last year, teed off from the 10th hole made the turn at 1 under after a birdie on the 16th.
But he started to unravel when he made a bogey at the first and then a triple bogey 7 on the third. The 25-year-old had back-to-back birdies from the seventh but closed with a second bogey of the day on the ninth.
"My putting was poor from start to finish," Matsuyama said. "There were many aspects of my shots that were not good so a score like this can't be helped.
"I was wondering why my shots were veering off. It is a disappointing score. I will try my best to get as many birdies as I can (over the next three days).
Daisuke Kataoka carded a 71 for a tie for 31st, while Hideto Tanihara and Shugo Imahira both shot even-par 72sto sit in a share of 48th.