If volatility is what the lords of the U.S. Open wanted, volatility is exactly what they’ve gotten this week at Shinnecock Hills.

On a third-round Saturday when it looked like Dustin Johnson, who slept on a four-shot lead and was looking unflappable for the first 36 holes, might waltz one round closer to his second U.S. Open win in the past three years, calamity ensued.

It was, indeed, a bizarre day at Shinnecock, where Johnson’s lead bled away like the nearby Atlantic Ocean tide going out to sea.

Tony Finau and Daniel Berger, who began the day 11 shots out of the led and tied for 45th, each shot 4-under-par 66s with early tee times and watched all afternoon as their names shot up the leaderboard.

How far up the leaderboard?

They’re tied for the lead at 3-over par and will be paired in the last group for Sunday’s final round.

Johnson shot 77 Saturday, the highest third-round score shot by a 36-hole leader since Harry Vardon shot 78 in 1913, and is tied for the lead along with defending champion Brooks Koepka, who shot 72.

Justin Rose, the 2013 U.S. Open winner, is one shot back at 4-over and Henrik Stenson is 5-over.
Kiradech Aphibarnrat, reigning Masters champion Patrick Reed and Jim Furyk, the current Ryder Cup captain who received a special exemption into the field, are 6-over and still very much in the tournament.

All 44 players in the last 22 groups shot rounds over par.

“I’ve never seen a golf course change that quickly,’’ Rose said.

“Some guys played well — Berger and Finau shot 4-under; obviously that’s great golf,’’ said Rickie Fowler, who began the day in contention and shot 84. “But that round was not out there this afternoon. And I’m not taking anything away from their rounds. The course changed and played a lot differently this afternoon.’’

Berger, after his 66 tied the low round of the tournament, was prescient when he said, “I think if someone shoots 4-under this afternoon, it’s more like an 8-under.’’

“I just went out there and played golf and added up the score at the end of the day and it happened to be a good one,’’ Berger said.

“I’m in a good position, in the lead [Sunday],’’ Johnson said. “I didn’t feel like I played badly at all. Seven over, you know, usually is a terrible score, but, I mean, with the greens the way they got this afternoon, I mean, they were very, very difficult.’’

Johnson, the 2016 U.S. Open winner, called it the best 77 he’s ever shot.

“I had six or seven putts that I could have easily putted right off the green,’’ he said, referring to the outlandish pin positions on some greens. “But it’s the U.S. Open. It’s supposed to be tough.’’

No one had a tougher day than Phil Mickelson, who turned 48 Saturday and is in pursuit of a U.S. Open win that would complete the rare career Grand Slam. He shot 81 thanks to a 10 he took on the 13th hole with a two-shot penalty for hitting a putt he’d struck that was still moving.

Andrew “Beef’’ Johnston, who was paired with Mickelson and had a front-row seat for the carnival show on 13, unwittingly captured the entire day best when he described Mickelson’s snafu.

“Just one of them mad moments,’’ Johnston said.

As they walked off the green toward the 14th tee together, Johnston said to Mickelson, “I’m sorry, but I’ve got to laugh at this.’’

“That’s one of the strangest things I’ve ever seen,’’ Johnston said. “It wasn’t a thing of saying, ‘I’ve had enough’ or this and that. It just happened. I’ve never seen anything like it. It’s something you might see at your home course with your mates or something. I think it’s just a moment of madness.’’

“Madness’’ was a good description of the day — one that ended with USGA executive director Mike Davis conceding that the organization miscalculated the wind conditions and set some pins that were unfair.

Johnston, who shot 82, one shot worse than Mickelson, said, “I think we were both happy to get off the golf course. It was more relief we got off the golf course, and now we can enjoy the afternoon.’’

Asked if laughing about their tough day “eased the pain’’ of the difficult day, Johnston said, “You have to. Otherwise, I’ll be crying. If you don’t laugh here, you’ll end up going insane.’’