Brooks Koepka made history for the second successive day at the US PGA Championship as he reached the halfway stage with a commanding seven-shot lead.
After breaking the course record with an opening round of 63, the defending champion followed up by signing for a 65 at Bethpage Black on Friday to leave him sitting pretty at the summit on 12 under par.
His combined total of 128 shots is the lowest after 36 holes at a major, a remarkable achievement at Bethpage Black – a course considered to be one of the toughest in the world.
Koepka had three birdies on his front nine as he went out in 32 and despite two dropped shots on the back nine – his first bogey of the tournament coming at the 10th hole – a three at the par-four 18th helped secure a comfortable cushion over nearest rivals Jordan Spieth and Adam Scott (64).
After winning by two last year from Tiger Woods – who missed the cut this time around – Koepka has clinically moved so far clear of the field this time around that a fourth career major now looks a formality.
No player has previously led by so many in US PGA history after two rounds, with the 29-year-old threatening to turn what was expected to be a gruelling battle for glory in New York into a title procession.
Spieth had appeared to surge into contention earlier in the day with a 66 to get to five under, with Scott later joining him in a share for second place. The Australian threatened to match or better Koepka's first round until a three-putt bogey at the 17th scuppered his record bid.
World number one Dustin Johnson (67) is one of five players sitting a shot further adrift, the American joined by compatriots Daniel Berger (66), Kelly Kraft (65) and Luke List (68), as well as Englishman Matt Wallace (67), while Justin Rose (67) sits alone on three under.
As for Woods (73), his hopes of playing over the weekend ended with three successive bogeys after the turn. The 15-time major winner was unable to find a birdie at the last to get the right side of the cut line, finishing up on five over.