SOUTHAMPTON, N.Y.—Nothing about the leaderboard at the U.S. Open on Saturday morning even remotely suggested that Daniel Berger and Tony Finau could be among the contenders to win it on Sunday. At 7 over par, 11 strokes off the lead, they had barely made the weekend cut.
But there are two ways to make up ground in a golf tournament. One is to go low, as Berger and Finau did by shooting 66s. The other is to sit back and watch as the rest of the field makes a mess of itself. At a sun-baked, wind-swept Shinnecock Hills Golf Club, Berger and Finau were able to do that, too.
The two young Americans catapulted into a four-way tie for the lead with Dustin Johnson and Brooks Koepka on a brutal day for scoring that left the entire field over par. Those four will begin the final round on Sunday at 3 over par for the tournament, one shot ahead of Justin Rose. Ten other players are within four shots of the lead.
Johnson, who won the tournament in 2016, teed off with the lead, lost it, regained it and finally settled into a tie with a bogey on the 18th hole. He stumbled to a 7-over-par 77, turning a potential Sunday rout into a free-for-all.
“I don’t feel like I played badly at all,” Johnson said. “Seven-over usually is a terrible score, but with the greens the way they got this afternoon, they were very difficult.”
Berger, 25 years old, and Finau, 28, are seeking their first career major titles. Koepka, 28, won at Erin Hills last June at 16 under par, tying the lowest winning score relative to par in tournament history. But he has earned little notice since. He missed the Masters with a wrist injury.
“There’s nobody more confident,” Koepka said. “I won this thing last year. I feel really good. My game’s in a good spot. I feel like you got to kind of take it from me, to be honest with you.”
After an easier day for scoring Friday, the course played faster and firmer on Saturday, eliciting at least one player complaint about the fairness of the setup.
“It’s pretty much gone. It’s pretty much shot,” Zach Johnson said after shooting a 72. “They’ve lost the golf course.”
But that sentiment wasn’t nearly as widely shared as it was in 2004, the last time the U.S. Open was played here. That year, the issue was the seventh green, which had been so under-watered that well-struck shots were bouncing off it.
There was no single flashpoint for player grumbling on Saturday, though a few mentioned the speed of the 15th green. As the final groups went around the course, grounds crews watered the greens behind them.
“It’s the U.S. Open. You know they’re trying to set this golf course up as close to the edge as possible,” said Jim Furyk, who shot a 72. However, he said, “This golf course has dried out significantly.”
More U.S. Open Coverage
It got worse as the day went on, to the significant advantage of Finau and Berger. Players who teed off in the morning scored more than two strokes better on average than those who teed off in the afternoon. “I’ve never seen a golf course change that quickly,” Rose said.
Dustin Johnson, the world No. 1, began the afternoon with a four-shot lead over Charley Hoffman and Scott Piercy. Considering Johnson’s level of talent, on a course where just making par is an ordeal for the world’s best players, it looked like a bigger lead than it was. But the possibility of a runaway victory faded quickly.
A big part of what put 33-year-old Johnson in the lead after the first two rounds was his putting, but that facet of his game got away from him early. On the par-3 second hole, from 28 feet, he three-putted for a double bogey. From there, he made four bogeys on the front nine to drop out of the lead.
Henrik Stenson briefly took the lead but made five bogeys on the back nine to finish the day in sixth place at 5 over. By then, Finau and Berger had been off the course for hours—the best place to be, as it turned out. They will have afternoon tee times on Sunday.
“This is what we play for,” Finau said. “This is what we practice for. Put ourselves in contention and just in a good position going into Sunday.”
Write to Brian Costa at brian.costa@wsj.com