ERIN, Wis. — The U.S. Open is supposed be tough with a course usually tricked up to make the world’s best golfers seem mortal.

Thursday, in the first round of the 117th gathering of this event, Rickie Fowler proved to be nearly immortal, tying a record that hadn’t been equaled in 37 years.

He birdied all four par fives, totaling 2,448 yards, and picked up three more on par fours to finish at 7-under, the lowest first-round score relative to par since Jack Nicklaus and Tom Weiskopf did it in 1980.

“It is always cool to be part of some sort of history in golf,” Fowler said. “But I’d rather be remembered for something that’s done on Sunday.”

Fowler benefited from more than solid shots and sharp putting. He played in the morning before the winds picked up, making both drives and approach shots more difficult.

But he wasn’t the only one to have a good round on a day when the USGA was likely red-faced over all the red numbers.

Paul Casey and Xander Schauffele sit one shot back, both playing in the late afternoon and early evening when the winds had subsided.

As is usually the case, the USGA will set up the course to play more difficult after Thursday. Forty-four players in the field of 156 were under par, beating the former record of 39.

The weather forecast has backed off the rain that was expected today and Saturday, allowing the greens to dry out and become more difficult to hold.

If you try and measure first-round success against the final outcome, realize that Nicklaus won the 1980 tournament at Baltusrol, but was just one shot better than his initial 18. Weiskopf went from 7-under to 8-over in his last 54 holes.

“I don’t need a whole lot more after putting seven up today,” Fowler said. “I’ll just take the cumulative of that for three days and I’ll wait and go over there and see what that does.”

Fowler has the ignominious title of being the best player to have never won a major, a label he inherited when Sergio Garcia won the Masters earlier this year.

It’s not that he hasn’t come close. In 2014, he finished fifth at the Masters, second at the U.S. Open and British Open and third in the PGA. He’s won four PGA Tour events, including the Honda Classic earlier this year.

“It was nice getting off to a quick start, birdieing 11, and kind of getting a bonus on 12 after hitting it in the first cut off the tee,” said Fowler, who started on the back nine.

“Then from there, I was just taking advantage of the par fives. So really I just had to add a couple more, and that was the round.”

Fowler had no bogeys. He birdied the 11th (6-foot putt), 12th (14 feet), 14 (12 feet) and was on the par-five 18th in two and two putted from 47 feet. Then, on the front side, he birdied one (7 feet), two (2 feet) and seven (13 feet).

He tees off at 2:36 p.m. today and will likely have to contend with tougher weather conditions.

Casey will switch to the morning with an 9:13 a.m. start and Schauffele at 9:46 a.m.

Casey, 39, had seven birdies and one bogey. He’s only won one tournament on the PGA Tour, with his best finish in a major being third in the 2010 British Open.

“I was hoping and praying I could get the same kind of conditions … and be half as good as Rickie Fowler,” Casey said. “So to be right behind him, I’m ecstatic.”

As much experience as Casey has, Schauffele lacks it. Schauffele, 23, is a San Diego native who played as a freshman at Long Beach State before transferring to San Diego State. His best ever finish on the Tour was a tie for fifth at the Sanderson Farms Championship in October. This is his second year on the Tour.

Schauffele had six birdies and no bogeys and missed a 16-foot putt for birdie on nine, his final hole, which would have put him in the record books with Fowler.

Schauffele conceded he was nervous playing in his first major.

“Walking over I was fine,” he said. “[But when they] announced my name I was a little more nervous. But when I got the first shot away and I was pretty much calm after that.”

Two shots back at five under are Tommy Fleetwood, Brian Harman and Brooks Koepka. Fleetwood and Harman had bogey-free rounds, while Koepka bogeyed the par-four eighth. All played in the morning.

“We had the best of conditions,” Fleetwood said. “This morning the breeze was the perfect amount, and it wasn’t strong enough to have any effect. And the course was as receptive as it’s going to be.”

Three shots back at 4-under were Patrick Reed, Marc Leishman, Kevin Na and Adam Hadwin. Everyone but Reed played in the afternoon.

Masters champion Sergio Garcia started off with an eagle on the par-five first hole but then his game flattened out with three birdies and three bogeys. He finished at 2-under.

In one of the odder stats, the top five players in the world finished at 19-over.

Among the most disastrous rounds was former world No. 1 Jason Day, who had two triple bogeys for the first time in his career. He finished the round at 8-over and is danger of missing the cut.

Rory McIlroy, considered one of the favorites, spent a lot of the afternoon in the deep fescue and finished at 6-over.

john.cherwa@latimes.com

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