Justin Thomas checks his lie on the second green during the first round of the US Open on Thursday in Mamaroneck, N.Y. (AP photo)

MAMARONECK, N.Y. — This wasn’t the kind of fun Justin Thomas had in mind for a U.S. Open at Winged Foot.

But he’ll take it.

For all the hype and history of how much punishment Winged Foot has doled out over the years. Thomas took advantage of a surprising soft and gentle Thursday morning with a 5-under 65, the lowest score in six U.S. Opens on this tough Tillinghast design.

All that got him was a one-shot lead over Patrick Reed, Thomas Pieters of Belgium and Matthew Wolff, the 21-year-old Californian making his U.S. Open debut.

Rory McIlroy was among those two shots behind on a scoreboard filled with red numbers, an unusual site at a Winged Foot course that has never yielded so many rounds under par — 21 — in the opening round of a U.S. Open.

He played with Masters champion Tiger Woods and PGA champion Collin Morikawa, who couldn’t get done fast enough.

Woods was in five bunkers through five holes and missed a putt on his final hole for a double bogey and round of 73.

Morikawa shot 76 and 50-year-old Phil Mickelson struggled to get to 79.