ERIN, Wis. — Just when it appeared the size of the moment might be getting to Brooks Koepka, he pulled out a 3-wood, gripped it and ripped it.

His ball sailed toward the green at the par-5 14th, and though it landed just short in the greenside bunker, it showed that Koepka wasn’t just trying to hang on to win the 117th U.S. Open. He was going to grab this tournament by the throat.

Koepka pitched out, drained the birdie, then carded another at the 15th, and the victory march was on.

In a matter of about 10 minutes, the U.S. Open went from being a four-horse slog to the finish to a rout. There would be no dramatic ending, no Monday playoff. Koepka made sure of that on 16 with yet another birdie, capping a three-hole stretch that will forever be etched in his memory as his greatest ever.

“We had to go out and try to win the tournament,” Ricky Elliott, Koepka’s caddy, told Yahoo Sports. “He’s been hitting the ball great all tournament, and he’s been putting great. He just stayed patient the whole time, and putts started going in there at the end.”

The fact that Koepka was 16-under par, with a chance to tie or best Rory McIlroy for the lowest total ever in a U.S. Open, mattered only in that he could ink his name on an all-time record. The more important number at that point was four, the number of strokes between Koepka and second place. By 17, with his ball safely on the green in two shots and the finish line in sight, Koepka received his first standing ovation from the crowd around the green.

For 17 holes, Koepka had been laser-focused, eschewing the high-five attempts that are always there on the walks from one green to the next tee. But as he walked to 18, and the hands reached out, Koepka finally obliged.

It was all over but the shouting, and as Koepka made the walk down the 681 yards that make up the 18th at Erin Hills, there was plenty of that. Shouts of “Take it home, Brooks!” and “That a boy, Brooks!” filled the Wisconsin afternoon, and chants of “KOEP-KAAAA!” (it’s “kept-kah, by the way) accompanied the impending champion as he approached the green.

Through three rounds, this U.S. Open had been characterized as “easy,” and upon first glance it might appear that way. Brian Harman’s score of 12-under after 54 holes put him in rarefied territory, a space where only Tiger Woods and McIlroy had gone before in the tournament’s previous 116 editions.

But on second glance, the world’s top three players (Dustin Johnson, McIlroy and Jason Day) were noticeably absent into the weekend. All three missed the cut, the first time that’s happened at any major tournament since the adoption of the ranking system in 1986. In total, eight of the world’s top 12 players missed the cut, and none inside the top five were ever in contention this week.

At the start of the day, nine players were within four shots of the lead. With wind blowing drives striped down the middle into the rough and pushing online putts offline, the tournament quickly transformed from a game of attack to one of survival.

Zach Johnson found this out early when his two-footer for par didn’t even threaten to hit the hole. Incredulous, Johnson walked away with his arms spread wide wondering aloud, “Whaaaaat?”

Eagle holes in the first three rounds suddenly became par holes, meaning birdies were tougher to come by.

But then the wind dropped, and the scores of the frontrunners did likewise. By the time the leaders made the turn on Sunday, just five players remained in realistic contention, within four strokes of the lead: Koepka, Harman, Rickie Fowler, Tommy Fleetwood and Hideki Matsuyama. Koepka held the outright lead at 14-under at the turn, with the remainder of the quintet fanned out behind. But he stumbled back to the field on the 10th, bogeying the hole to fall into a tie with Harman.

Fowler’s chances faded on the 12th when he ran a birdie putt 12 feet by the hole, then missed the par comeback to fall three shots back. He later bogeyed 15, effectively ending his chances at victory. Erin Hills marked the second straight major Fowler went into Sunday with a shot at his first major, only to fail once again to break par. Fleetwood could never make any kind of move, treading water as Koepka cruised ever farther ahead.

Koepka retook the outright lead with a key par save on 13 at the same time as Harman carded his first back-nine bogey of the week at 12. Five holes ahead, Matsuyama closed out a round of 66 and posted the target score: 12-under par.

Right about then, the pressure seemed to begin cinching around Harman’s neck. He bogeyed the 13th, missing a makeable three-foot putt, dropping him two strokes behind Koepka and one behind Matsuyama. Shortly afterward, Koepka turned a sand save into that handy birdie on the 14th, extending his lead to two strokes over Matsuyama’s signed card.

Harman birdied the 14th, tying with Matsuyama and closing back to within two strokes of Koepka. But barely a minute later, Koepka birdied 15, the toughest hole on the course, to open up a three-stroke lead with three holes to play.

“The shot into 15 was unbelievable because we were kind of in-between numbers, and he must have taken 15 yards off the iron,” Elliott said. “I don’t know how he did it, but it was his best shot of the day.”

Koepka then birdied the 16th, and it was time for the engraver to start assembling the proper letters. At that point, the only question was whether Koepka would best McIlroy’s record of 16-under for the lowest score to par, set in 2011.

A birdie on 16 edged Harman back past Matsuyama, but was too little, too late. Koepka’s birdie streak ended with a par on 17 and he walked to the 18th with a three-stroke lead. About 20 minutes later, the trophy was his.

On a day when just 50 of the 68 players shot par or worse, when many who started atop the leaderboard retreated, Brooks Koepka shot a 5-under 67, good for 16-under and tying him with McIlroy for the record.

That’s not having the U.S. Open fall in your lap. That’s going and getting it. And on Sunday, Brooks Koepka went and got it.