Fowler needed to birdie the par-4 18th hole at Los Angeles Country Club to break the 36-hole record set by Martin Kaymer at Pinehurst No.2 in 2014. But he settled for a two-putt par, one of only four pars he made in the second round.

Fowler had eight birdies and six bogeys and, after opening with three straight birdies, he also became the fastest player in history to reach 11-under at a U.S Open.

“It's not that easy out there,” Fowler said. “I've made a lot of birdies and that is doable out there. Until you've been on the grounds or been out there hitting shots, it's still a very hard test.

“Is it the hardest U.S. Open? No. I think it's a good, fair, hard test. Visually probably watching on TV and stuff it probably doesn't do it justice. The fairways look very wide because yes, the mowed areas are wide, but where you have to hit it is very small. So the golf course is big and open but plays very tight.”

The 34-year-old Fowler, from Murrieta about 100 miles south of Los Angeles, is trying to win his first major. He leads Wyndham Clark by one stroke, with Rory McIlroy another shot back.

“I'm looking forward to the weekend. It's been a while since I've felt this good in a tournament, let alone a major. It's going to be a challenge, but I'm definitely looking forward to it.” – Rickie Fowler.

Fowler and Xander Schauffele each shot 62 in the opening round, breaking the previous U.S Open record.

Fowler didn't qualify for the last two U.S Opens. But he's been strong this tournament.

“I sure hope everyone can relate to struggles because everyone deals with them,” Fowler said Friday. “No one's perfect. I think you'd be lying if you haven't been through a tough time, especially if you play golf.

“I'm looking forward to the weekend. It's been a while since I've felt this good in a tournament, let alone a major. It's going to be a challenge, but I'm definitely looking forward to it.”

Schauffele, who was two groups behind Fowler, made three straight bogeys on the back nine.

He eventually signed for a 71 to be sharing fourth at seven-under with Harris English (66).

Australian Min Woo Lee had the low round of the day to move to six-under and into a tie for sixth with former World No.1 Dustin Johnson, who rebounded from a quadruple-bogey eight at the 2nd hole to card a fighting even-par 70.

World No.1 Scottie Scheffler and former amateur star Sam Bennett are tied for eighth at five-under following rounds of 68.

Australia's World No.9 Cameron Smith (67) is outright 10th at four-under.