Bethpage - Defending champion Brooks Koepka completed the lowest 36-hole showing in major golf history on Friday to seize a record seven-stroke lead after two rounds of the PGA Championship while Tiger Woods missed the cut.
Third-ranked Koepka, a runaway favourite to capture his fourth major title on Sunday, fired a five-under par 65 on Friday at Bethpage Black to stand on 12-under 128.
His devastating two-day performance produced the largest halfway lead in modern major golf history. The biggest prior 36-hole PGA lead had been Zimbabwean Nick Price's five-shot edge in 1994.
And Koepka was disappointed in two bogeys that cost him an even tighter stranglehold.
"Today was a battle. I was fighting," Koepka said. "I feel good, especially the way I battled today. I fought hard. I feel great. Just need to continue on the weekend."
The lowest prior halfway score in major golf history was 130, managed five times, including by American Gary Woodland at last year's PGA.
Koepka, who set the course record with a 63 on Thursday, birdied three of the first four holes and four of the last six Friday to complete the most overpowering start even seen in major golf.
"I'm still putting very well," he said. "I'm still hitting my lines and reading my putts very well."
If he does claim the Wanamaker Trophy and a $1.98 million top prize, he'll be the first man to defend US Open and PGA titles in his career and the first to own back-to-back titles in two majors at the same time. He'd be the first to the defend the PGA title since Woods in 2007.
Woods struggled in his first event since ending an 11-year major win drought by capturing last month's Masters for his 15th major title.
"Just didn't quite have it," Woods said after firing a 73 to stand on 145, one over the cut line. "Did a lot of little things wrong.
"There's no reason I can't get up to speed and start cranking it back up again. I've got to start feeling better first."
American Jordan Spieth, trying to win to complete a career Grand Slam, and Australia's Adam Scott shared second on 135.
Spieth, who hasn't had a top-20 finish all year and hasn't won since the 2017 British Open, shot 66 while Scott fired a 64, a bogey at the par-3 17th costing him a share of the course record.
Matt Wallace, trying to become the first Englishman to win the PGA since Jim Barnes in 1919, shared fourth on 136 with Americans Kelly Kraft, Luke List, Daniel Berger and Dustin Johnson. Second-ranked Justin Rose of England was ninth on 137.
World No 1 Johnson is in danger of losing the top spot to Koepka, a 29-year-old American who goes for a third consecutive US Open title next month at Pebble Beach.
Scott flirted with the all-time major low round of 62 set by South African Branden Grace at the 2017 British Open, but lipped out a short par putt at 17.
"I played fairly solid. It was nice to keep momentum going," Scott said. "It was nice to post a number but it looks like I'll have to post two more pretty good numbers at this stage."
Spieth has developed faith in his swing after months of uncertainty.
"Confidence has been there," Spieth said. "I figured if I stayed out of my own way, stick to one thought, (my game) was in good enough shape to contend."
Spieth could become only the sixth golfer to win each of the four majors at least once, joining Tiger Woods, Jack Nicklaus, Gary Player, Gene Sarazen and Ben Hogan.
"I haven't been in contention since the Open last year," Spieth said. "If I put in some good work tomorrow I'll be in contention on Sunday."
But he isn't counting on Koepka backing up.
"You don't expect Brooks to fall at all," Spieth said. "I felt like I had to be within six or seven going into the weekend."
Johnson, whose only major title came at the 2016 US Open, reeled off five birdies in seven holes in one stretch.
"I'm pleased with the score and pleased with how I played," said Johnson. "I'm going to need to play the next two days the way I've played the first two days."
Four-time major winner Rory McIlroy was one inside the cut line on 143, among 82 to reach the weekend.
Scores after Friday's second round of the 101st PGA Championship at par-70 Bethpage Black:
128 - Brooks Koepka (USA) 63-65
135 - Jordan Spieth (USA) 69-66, Adam Scott (AUS) 71-64
136 - Daniel Berger (USA) 70-66, Dustin Johnson (USA) 69-67, Kelly Kraft (USA) 71-65, Matt Wallace (ENG) 69-67, Luke List (USA) 68-68
137 - Justin Rose (ENG) 70-67
138 - Danny Lee (NZL) 64-74, Kang Sung (KOR) 68-70, Jazz Janewattananond (THA) 70-68, Harold Varner (USA) 71-67, Erik Van Rooyen (RSA) 70-68, Tommy Fleetwood (ENG) 67-71, Louis Oosthuizen (RSA) 70-68, Rickie Fowler (USA) 69-69, Hideki Matsuyama (JPN) 70-68
139 - Patrick Cantlay (USA) 69-70, Bronson Burgoon (USA) 73-66, Scott Piercy (USA) 72-67, Mike Lorenzo-Vera (FRA) 68-71, Chez Reavie (USA) 68-71, Xander Schauffele (USA) 70-69, Charles Howell (USA) 72-67
140 - Matt Fitzpatrick (ENG) 75-65, Gary Woodland (USA) 70-70, Keegan Bradley (USA) 70-70, Zach Johnson (USA) 71-69, Phil Mickelson (USA) 69-71, Matt Kuchar (USA) 70-70, Jimmy Walker (USA) 70-70, Tyrrell Hatton (ENG) 71-69, Francesco Molinari (ITA) 72-68, Lucas Bjerregaard (DEN) 71-69
141 - Ross Fisher (ENG) 74-67, Lucas Glover (USA) 72-69, Paul Casey (ENG) 70-71, Danny Willett (ENG) 71-70, Webb Simpson (USA) 72-69, Pat Perez (USA) 68-73, Beau Hossler (USA) 72-69, Brandt Snedeker (USA) 74-67, Max Homa (USA) 70-71, Aaron Wise (USA) 70-71, Marty Jertson (USA) 72-69
142 - Joel Dahmen (USA) 70-72, Billy Horschel (USA) 70-72, Kurt Kitayama (USA) 74-68, Adam Hadwin (CAN) 72-70, Sam Burns (USA) 70-72, Henrik Stenson (SWE) 74-68, Charley Hoffman (USA) 73-69, Graeme McDowell (NIR) 70-72, Alex Noren (SWE) 73-69, Li Haotong (CHN) 73-69
143 - Jason Kokrak (USA) 73-70, Tony Finau (USA) 70-73, Thorbjorn Olesen (DEN) 73-70, Cameron Champ (USA) 72-71, Emiliano Grillo (ARG) 76-67, Kevin Tway (USA) 73-70, Rory McIlroy (NIR) 72-71, Jason Day (AUS) 69-74, Cameron Smith (AUS) 73-70, Abraham Ancer (MEX) 73-70, Adam Long (USA) 73-70
144 - Ryan Vermeer (USA) 70-74, Rich Beem (USA) 75-69, Rafa Cabrera Bello (ESP) 75-69, Corey Conners (CAN) 72-72, J.J. Spaun (USA) 72-72, Rob Labritz (USA) 75-69, Thomas Pieters (BEL) 74-70, Kiradech Aphibarnrat (THA) 76-68, Andrew Putnam (USA) 74-70, David Lipsky (USA) 70-74, Justin Harding (RSA) 74-70, Shane Lowry (IRL) 75-69, J.T. Poston (USA) 77-67, Lucas Herbert (AUS) 74-70, Joost Luiten (NED) 72-72
Missed the cut
145 - Adrian Otaegui (ESP) 73-72, Steve Stricker (USA) 73-72, Martin Kaymer (GER) 74-71, Kevin Na (USA) 72-73, Ryan Armour (USA) 74-71, Tyler Hall (USA) 72-73, Michael Kim (USA) 74-71, Jon Rahm (ESP) 70-75, Jim Furyk (USA) 73-72, Dylan Frittelli (RSA) 77-68, Patton Kizzire (USA) 70-75, Keith Mitchell (USA) 74-71, Kyle Stanley (USA) 71-74, Sergio Garcia (ESP) 74-71, Bubba Watson (USA) 76-69, Russell Knox (SCO) 72-73, Tiger Woods (USA) 72-73, Julian Suri (USA) 72-73, Martin Trainer (USA) 75-70, Im Sung-jai (KOR) 71-74
146 - Branden Grace (RSA) 73-73, Ian Poulter (ENG) 72-74, Kim Si-woo (KOR) 69-77, Bryson DeChambeau (USA) 72-74, Richy Werenski (USA) 72-74, Patrick Reed (USA) 74-72, Joaquin Niemann (CHI) 75-71
147 - Tom Lewis (ENG) 76-71, Ben Cook (USA) 74-73, Lee Westwood (ENG) 75-72, Shaun Norris (RSA) 73-74, Shugo Imahira (JPN) 74-73, Troy Merritt (USA) 72-75, Brian Mackey (USA) 74-73
148 - Mikko Korhonen (FIN) 74-74, Marc Leishman (AUS) 74-74, An Byeong-hun (KOR) 74-74, Richard Sterne (RSA) 75-73, Jason Dufner (USA) 76-72, Ryan Fox (NZL) 78-70, J.B. Holmes (USA) 71-77
149 - Michael Thompson (USA) 77-72, Pan C.T. (TPE) 78-71, Satoshi Kodaira (JPN) 73-76, Chesson Hadley (USA) 72-77, Jason Caron (USA) 70-79
150 - Justin Bertsch (USA) 77-73, Ryan Moore (USA) 73-77, Jorge Campillo (ESP) 77-73, Casey Russell (USA) 77-73
151 - Eddie Pepperell (ENG) 76-75, Yang Yong-eun (KOR) 76-75, John Daly (USA) 75-76, Rich Berberian (USA) 76-75
152 - Alex Beach (USA) 77-75, Ryan Palmer (USA) 77-75, Padraig Harrington (IRL) 75-77, Brandon Stone (RSA) 79-73
153 - Jhonattan Vegas (VEN) 76-77, Kevin Kisner (USA) 77-76, Craig Bowden (USA) 78-75
154 - Rod Perry (USA) 77-77, Brian Harman (USA) 77-77, Shaun Micheel (USA) 77-77
155 - Alex Bjork (SWE) 80-75, Danny Balin (USA) 78-77, Brendan Jones (AUS) 78-77
157 - John O'Leary (USA) 79-78
158 - Stuart Deane (AUS) 82-76
159 - Craig Hocknull (AUS) 82-77, Jeffrey Schmid (USA) 81-78, Cory Schneider (USA) 74-85
166 - Andrew Filbert (USA) 84-82