– Two-time U.S. Open champion Brooks Koepka took a step toward adding a third major championship Sunday, then took a half-step back.

Koepka bullied rain-softened Bellerive on the front nine and built a four-shot lead, only to run into bad patch that brought a strong list of contenders into the mix — including Tiger Woods — going into the final round of the PGA Championship.

Even with back-to-back bogeys on the back nine, Koepka had a 4-under 66 for a two-shot lead over Adam Scott, the 2013 Masters champion. Scott had a 65 to get into the final group.

Gary Woodland lost his way in his footprints in a bunker and made triple bogey on No. 10, falling six shots behind, and still managed a 71 to stay within three shots of the lead, along with Jon Rahm and Rickie Fowler.

But the biggest buzz belonged to Woods.

Coming off a three-putt bogey on the fifth hole, Woods ran off three straight birdies to get in range, only to stall on the back nine. He hit a 4-iron so pure on the par-5 17th hole that he immediately began walking off to it, and thousands of fans roared when it settled 20 feet from the hole for an eagle putt that could have brought him within one of the lead.

He missed. And then he missed the next from 4 feet for birdie and ended his day with 10 straight pars. Woods had to settle for a 66, and by the time everyone else came through the 17th hole, he was tied for sixth, four shots out of the lead.

That's the same position he was in going into the final round of the British Open at Carnoustie, where he led briefly in the final before fading.Now he gets another shot, and it most likely will take another round like Saturday's.

"Everyone's going to have to shoot low rounds," Woods said. "It's soft, it's gettable, and you can't just go out there and make a bunch of pars."

Koepka was at 12-under 198 and will play in the final group of a major for the first time. He won in the penultimate group at the U.S. Open each of the past two years.

He already burnished his reputation two months ago by winning a U.S. Open on two entirely different courses — one at Erin Hills with a record-tying score of 16 under par, the other at Shinnecock Hills, where he survived to win at 1 over par.

He has only one other PGA Tour victory, one in Europe and two in Japan. But put him against the strongest fields and the biggest events, and he's a world-beater.

This test figures to be different.

"I've watched Tiger win 14 of these things hanging around a lot of the time," Scott said. "He ran away with a few, for sure, but he hung around for a lot. And I would love to hang around tomorrow. And that might mean shooting 5 under again to hang around, but I would love to be in the mix coming down the stretch."

Ten players were within four shots of the lead, including defending champion Justin Thomas (68), Jason Day (67) and Stewart Cink, the 2009 British Open champion who played with Woods and matched his 66.

"It's a pretty intense environment out there. It's fun," Cink said. "Hearing the crowd, and Tiger's performing great, it was like turning back the hands of the clock."

As easy as it looks at times, Bellerive can still bite at any moment.

Jordan Spieth found that out on a hole that effectively ended his second bid for the career Grand Slam. From well right of the 12th fairway, he tried to hit through a gap and instead his ball caromed off a tree and out of bounds, leading to triple bogey and dropping him to 4 under for the tournament.

No one paid more dearly than Woodland. Three shots behind at the turn, he and Kevin Kisner were in a front bunker. Woodland went over the green onto a slope at the back of another bunker, and his next shot went through the green back into the first bunker. The sand had yet to be raked, and Woodland's ball was in his footprints.

He wound up with triple bogey, and scrambled to get back in the mix. "Really confident going into tomorrow with the way I fought the last eight holes," he said.