SHANGHAI • Dustin Johnson charged into a six-shot lead at the WGC-HSBC Champions in Shanghai yesterday, after Brooks Koepka endured a nightmare stretch from holes No. 8 to No. 12.
In breezy conditions, Johnson's four-under 68 widened his one-shot overnight lead on his fellow American, who shot an error-strewn 73.
His 17-under total of 199 puts him in pole position to notch his third World Golf Championship (WGC) title of the year.
The world No. 1 identified the eighth hole as the turning point and Koepka called his five-hole stretch from that point "a disaster".
Johnson made birdies at the par-five second, the par-three fourth, par-four seventh and par-five eighth, where Koepka's challenge faltered badly with a triple bogey.
The world No. 11 drove into the trees on the left. Then, from the middle of the fairway, he put his fourth shot into a thicket of trees left of the green and had to traipse some 70m back to take a drop shot.
Johnson had also miscued his approach to the left but was saved from the trees by a fortunate bounce.
He then rubbed salt into his good friend's wounds by rolling in a sublime, breaking 20-foot putt for birdie.
"I don't know what happened from No. 8 on," said Koepka. "It was kind of very disappointing - very blah. I didn't really make any putts, like those momentum putts. I didn't make one of those."
He said he had been put off on the par-five 18th hole, where he stumbled to a third bogey of the day, by multiple cameras going off.
Third at Sheshan International Golf Club, seven shots behind Johnson, was last year's runner-up Henrik Stenson (69) of Sweden.
Said Johnson on his mindset going into the decisive day with such a big lead: "I'm not worried about what anyone else is doing, I've got enough to worry about with just myself.
"I'm not going to change my game plan playing no matter what Brooks does, Henrik, whoever is out there playing.
"I'm going to stick to it and hopefully execute."
Hideki Matsuyama, the reigning champion from Japan, had another poor day with a 72 to leave him firmly out of the reckoning at the US$9.75 million (S$13.3 million) event.
AGENCE FRANCE-PRESSE, REUTERS
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