Brooks Koepka made a good start to his bid for an historic third straight victory in the US PGA Championship as Tiger Woods kept himself in contention in San Francisco.
Former world No1 Jason Day and American Brendon Todd shared the lead on five under par, with Koepka part of a nine-strong group on four under which included Olympic champion Justin Rose and two-time major winner Martin Kaymer.
England's Tom Lewis was two shots behind following a 67, with Open champion Shane Lowry alongside Woods on two under par.
Starting on the back nine, Koepka failed to take advantage of the par-five 10th and dropped a shot on the next, but then birdied the 13th, 14th, 16th and 18th.
A bogey on the first slowed Koepka's momentum, although he did well to limit the damage to a single shot.
"I feel good. I feel confident. I'm excited for the next three days," Koepka was quoted as saying by the Press Association. "I think I can definitely play a lot better, and just need to tidy a few things up, and we'll be there come Sunday on the back nine."
Woods was two under par after four holes, fell back to level par and then fired three birdies in four holes before making a bogey on his penultimate hole.
The 15-time major winner, who is using a slightly longer putter to ease the strain on his troublesome back, said: "It's difficult for me to bend over at times, and so practicing putting, I don't spend the hours I used to.
"It wasn't unusual for me to spend four, five, six hours putting per day. I certainly can't log that with my back being fused. Most of the guys on the Champions Tour have gone to longer putters as they have gotten older, because it's easier to bend over, or not bend over."
