Zalatoris, who lost in a three-hole play-off at the PGA Championship last month, made only one bogey – a staggering feat on a beast of a Brookline course – for a three-under 67 on Saturday.

"Felt like I shot a 61," Zalatoris said.

"Whenever I made a mistake I was able to get away with it or pull off something miraculous."

Fitzpatrick, already a champion at The Country Club with his U.S. Amateur title in 2013, was equally steady and ran off three birdies over his last five holes for a 68. He will be in the final group of a major for the second straight time.

Most telling was they didn't make any double bogeys.

Matt Fitzpatrick will play in the final group for the second straight major on Sunday. PHOTO: USGA.

That's what knocked defending champion Jon Rahm out of the lead on the final hole. The Spaniard thought he had seen it all – including a shot he played back-handed from the base of a tree on the 8th hole – when he took three swipes from sand in two bunkers.

Rahm's first shot from a fairway bunker hit the lip and nearly rolled into his footprint. His next shot found a plugged lie in a greenside bunker, and two putts later he had a 71 and went from one ahead to one behind.

"I have 18 holes, and I'm only one shot back," he said.

"That's the important thing."

Min Woo Lee is the pick of the Australians in a tie for 17th at two-over after his third-round 69. Adam Scott (72) and Marc Leishman (73) are four-over and Todd Sinnott (74) six-over.

Zalatoris and Fitzpatrick were at four-under 206, the same score of the 54-hole lead when the U.S. Open was last at The Country Club in 1988.

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Brookline was so wild that Rahm was among eight players who had at least a share of the lead at some point. Three of them didn't even finish among the top-10, including two-time major champion Collin Morikawa.

Morikawa, who shared the 36-hole lead with Joel Dahmen, had double bogeys on the 7th and 13th holes, and might have had a third after a chunked wedge on No.4 except that he made a 25-foot putt for bogey. He finished with a 77 and is two-over.

Masters champion Scottie Scheffler was not immune. The World No.1 shot 71 and is tied for fourth at two-under while Rory McIlroy (73) made one birdie in his round to be three off the pace at one-under.

"It was one of the toughest days on a golf course I've had in a long time," McIlroy said.

"I just needed to grind it out, and I did on the back nine. To play that back nine at even par today was a really good effort, I thought. Just kept myself in the tournament. That's all I was trying to do. Just keep hanging around."

Twenty-three players were under par going into the third round. Only nine remain with 18 holes remaining, all of them separated by three shots.