U.S. Open champion Brooks Koepka revealed a phone call from Dustin Johnson helped him stay patient during the final round at Erin Hills.

Koepka, 27, claimed his first major on Sunday, carding a five-under 67 in the final round to secure a four-stroke victory.

The American's success came a year on from Dustin Johnson winning his maiden major at Oakmont.

Koepka said the world number one had called him on Saturday, offering some advice which came in handy.

"[I was] just staying one shot at a time. That's what I kept doing," he told a news conference.

"Dustin actually called me last night and told me the same thing, just stay patient. Just keep doing what you're doing, you're going to win the thing, and just don't get ahead of yourself. A bunch of people told me that.

"And I felt like I really stayed patient all week. Between conversations I've had with Claude [Harmon III] and Pete Cowan sat me down, I think, on Tuesday, and kind of had a conversation with me just kind of staying patient, not trying to win.

"I felt like that has been the thing lately with me, why I haven't really played that well, I've been trying to win so badly. I felt like I've underachieved. And the more patient that I can become, the more times I'll put myself in this situation."

Koepka finished at 16 under – well clear of Hideki Matsuyama and Brian Harman – as he equalled Rory McIlroy's record score to par in the tournament's history.

He said Johnson, one of several big names to stunningly miss the cut, was supportive after the pair played a round together ahead of the event.

"I mean there's probably not that much that's that interesting, to be honest. It was a long phone call. For us it was like two minutes, it wasn't much," Koepka said.

"But he just said a few things, and just stay patient. And I'll win if I stay patient and just keep doing what I'm doing.

"Because we played Tuesday practice round together and, I mean, he watched me play. I thought I played pretty solid on Tuesday. And he said he was pulling for me and just hang in there. It will happen."