FARMINGDALE, N.Y.: Brooks Koepka planted one hand firmly on the Wanamaker Trophy when he shattered the record books en route to a seven-stroke lead following the second round at the PGA Championship on Friday.
A day after a course-record 63 at Bethpage Black, the American carded five-under-par 65 to post the lowest score for the first 36 holes in major championship history.
At 12-under 128, he also secured the biggest ever halfway lead at a PGA Championship.
Koepka had started the day one stroke ahead but ended it surely two solid rounds from becoming the first player to hold back-to-back PGA Championship and U.S. Open titles at the same time.
Koepka, however, said Friday's round was still a struggle.
"This probably sounds bad, but today was a battle," he said. "I didn't strike it that good.
"I was leaking a few to the right but the way I hung in there today and battled it, I think that was probably more impressive than yesterday, not having your 'A' game but still being able to shoot a great score.
"I was very, very pleased with the way I played today."
Grand slam-seeking Jordan Spieth (66) and Adam Scott (64) were equal second on five-under, with world number one Dustin Johnson (67) part of a group eight behind.
Tiger Woods missed the cut in his first start since winning the Masters a month ago, putting poorly in the first round and driving badly in the second to record a five-over 145 score.
Playing in the same group as Koepka, 43-year-old Woods looked a shadow of the man who memorably grabbed a 15th major title at Augusta National.
Woods was certainly impressed by Koepka.
"He's driving it 330 yards in the middle of the fairway," Woods said. "He's got nine-irons when most of us are hitting five-irons, four-irons, and he's putting well.
"That adds up to a pretty substantial lead, and if he keeps doing what he's doing, there's no reason why he can't build on this lead."
Koepka showed from the start he was not going to abandon his attacking philosophy on Friday.
Taking advantage of the relatively easy early stretch, he plundered birdies at three of the first four holes, and then added four more in the closing six holes.
His bogey at the 10th was his first in his two rounds, while he also dropped a shot at the 17th.
He enjoyed a slice of luck at the last when his approach barely cleared the long grass in front of the green, but the ball bounded forward and he cashed in by sinking the 10-foot birdie putt.
Earlier, Spieth, who would complete the career grand slam with a win, showed signs of emerging from a season-long funk and for a while looked like being within striking distance of Koepka.
"I made a few good par-saving putts and took advantage of the easy holes," said the Texan.
"This golf course you can't (force it). It requires more patience which feeds into what I'm trying to do."
Scott, who like Koepka played in the afternoon, crept within four shots at one stage as the putter ran hot.
But the 2013 Masters champion missed a two-footer at the penultimate hole which cost him a chance to match Koepka's course record.
Despite the deficit, Scott was not ready to concede the title to Koepka.
"If he doesn't have a hot day tomorrow, the gap narrows and there's pressure over whatever lead he might have or might not on Sunday," Scott said.
"I know he's won three majors. I know he seems impenetrable at the moment in this position, but at some point he's got to think about it."
(Reporting by Andrew Both; Additional reporting by Frank Pingue in Toronto; Editing by Toby Davis/Greg Stutchbury)