World number one Justin Thomas was left kicking himself after a late stumble thwarted a blistering third round charge at the PGA Championship on Saturday.
Thomas looked poised to have a big moving day after notching birdies on five of his first seven holes en route to a two-under-par 68 at TPC Harding Park.
But he couldn't maintain that pace on the back nine and closed with two bogeys in his final three holes.
"I am pissed off. It is the best way to describe it," the American said. "I let a really good round go. I just didn't capitalize on a good start."
Thomas is at one-under 209, still seven shots back of second round leader Li Haotong of China, who has a late afternoon tee time.
Thomas, playing in a marquee group with Tiger Woods and Rory McIlroy through the first two rounds, shot 71 and 70 and only just made the cut on the line at one over to get into the weekend.
"I knew I needed to post a good round to have a chance and I got off to the start I wanted ... It is a bummer," he said.
On Saturday, Thomas opened with a par on No. 1 but then made a nine-foot putt for birdie on the par-four second.
He two-putted for birdie on the par-five No. 4 and then drained an 11 footer on the fifth to move to two-under for the tournament.
He also birdied par-four No. 6. He lost some ground with back-to back-bogeys on No. 8 and No.9, but tapped in his sixth birdie of the day on the par-five No. 10 to get to four under for the round.
Thomas flirted with another birdie on the par-three No. 11. He took an aggressive line, hitting into a cross wind at a pin tucked into the right corner of the green behind a sizeable bunker.
His ball sailed straight at the pin and landed nine feet from away for another birdie opportunity.
But his putt missed just left, leaving him with a tap in and an indication of things to come.
"I felt like I would have been in a great position going into the last round," he said. "You can't take any breathers on this course. You have to really pay attention to every shot, every putt."
Leading scores after Saturday's third round of the PGA Championship at par-70 TPC Harding Park in San Francisco:
201 - Dustin Johnson (USA) 69-67-65
202 - Scottie Scheffler (USA) 66-71-65, Cameron Champ (USA) 71-64-67
203 - Brooks Koepka (USA) 66-68-69, Collin Morikawa (USA) 69-69-65, Paul Casey (ENG) 68-67-68
204 - Justin Rose (ENG) 66-68-70, Tommy Fleetwood (ENG) 70-64-70, Daniel Berger (USA) 67-67-70, Bryson DeChambeau (USA) 68-70-66, Tony Finau (USA) 67-70-67, Jason Day (AUS) 65-69-70
205 - Li Haotong (CHN) 67-65-73, Kim Si-Woo (KOR) 69-68-68, Joel Dahmen (USA) 69-68-68, Xander Schauffele (USA) 66-70-69, Matthew Wolff (USA) 69-68-68
206 - Hideki Matsuyama (JPN) 70-67-69, Michal Lorenzo-Vera (FRA) 66-68-72, Bernd Wiesberger (AUT) 68-68-70
207 - Jon Rahm (ESP) 70-69-68, Dylan Frittelli (RSA) 70-67-70, Webb Simpson (USA) 71-68-68, Brendon Todd (USA) 65-70-72, Patrick Reed (USA) 68-70-69, Patrick Cantlay (USA) 73-68-66, Lanto Griffin (USA) 68-68-71, Harold Varner III (USA) 72-66-69, Ian Poulter (ENG) 73-68-66
208 - Kevin Kisner (USA) 67-73-68, Keith Mitchell (USA) 68-72-68, Victor Perez (FRA) 70-69-69, Adam Scott (AUS) 68-70-70
209 - Adam Hadwin (CAN) 68-71-70, Charl Schwartzel (RSA) 73-68-68, Shane Lowry (IRL) 68-72-69, Alexander Norn (SWE) 67-69-73, Nate Lashley (USA) 69-70-70, Justin Thomas (USA) 71-70-68, Harris English (USA) 69-71-69, Brendan Steele (USA) 66-71-72, Denny McCarthy (USA) 70-69-70
210 - Brandt Snedeker (USA) 72-66-72, Brian Harman (USA) 68-71-71, Bud Cauley (USA) 66-71-73, Kurt Kitayama (USA) 68-72-70, Doc Redman (USA) 73-67-70, Rory McIlroy (NIR) 70-69-71, Mackenzie Hughes (CAN) 73-68-69, Cameron Smith (AUS) 71-69-70, Emiliano Grillo (ARG) 70-70-70
211 - Abraham Ancer (MEX) 69-70-72, Louis Oosthuizen (RSA) 70-71-70, Phil Mickelson (USA) 72-69-70, Luke List (USA) 72-69-70, Billy Horschel (USA) 69-71-71, Russell Henley (USA) 71-69-71, Mark Hubbard (USA) 70-71-70
212 - Tiger Woods (USA) 68-72-72, Kevin Streelman (USA) 69-70-73, Gary Woodland (USA) 67-72-73, Jim Herman (USA) 71-69-72, Tom Hoge (USA) 72-68-72, Viktor Hovland (NOR) 68-71-73, Joost Luiten (NED) 71-68-73, An Byeong-hun (KOR) 72-69-71, Sepp Straka (AUT) 70-71-71
213 - Rory Sabbatini (SVK) 71-70-72, Adam Long (USA) 73-68-72
214 - Bubba Watson (USA) 70-71-73, Robert MacIntyre (SCO) 73-67-74, Danny Lee (NZL) 69-71-74
215 - Erik Van Rooyen (RSA) 71-70-74, Matt Wallace (ENG) 71-70-74
216 - Chez Reavie (USA) 71-70-75, Ryan Palmer (USA) 74-66-76, JT Poston (USA) 67-74-75
217 - Jordan Spieth (USA) 73-68-76, Kang Sung-hoon (KOR) 70-71-76