- Justin Thomas shoots US Open record nine-under 63
- Brian Harman leads at 12 under
- Thomas, Fleetwood, Koepka 11 under
(CNN)You wear pink slacks, you'd better be good.
Justin Thomas is good. So good he set a new record for the lowest round in relation to par in US Open history.
The 24-year-old eagled the 18th to shoot a spectacular nine-under 63 on day three at Erin Hills.
"Oh gosh, Jimmy, be good," the American said to his caddie as he unleashed his three-wood second shot 310 yards on the 667-yard par-five final hole.
It was better than that. The ball soared into the Wisconsin sky and landed on the front of the green, took a couple of hops and settled eight feet past the pin.
Thomas and his trousers rolled it in to ground-rattling roars to beat the previous best of countryman Johnny Miller, who shot an eight-under 63 on the par-71 Oakmont in 1973.
The young American fired nine birdies, two bogeys and an eagle to become the 29th player to score 63 in a major, and only the fifth at a US Open.
And all on the longest ever course in US Open history, albeit in calm conditions and softened by overnight rain.
"Once I found out it was on the green I said to Jimmy, 'Come on, let's be a part of history,'" said world No. 13 Thomas, who became only the seventh player in PGA Tour history to shoot a 59 when he broke the iconic 60 barrier in the Sony Open in Hawaii in January.
"It's obviously a great honor to have."
Harman leads into Sunday
And yet Thomas wasn't even leading going into the final round.
He was overtaken by compatriot Brian Harman and Englishman Tommy Fleetwood, who nudged the lead to 12 under before Fleetwood slipped up on the final hole.
Left-hander Harman, ranked 50th in the world, parred the last for a 67 and a one-shot lead over Thomas, Fleetwood and Brooks Koepka at 11 under.
The 30-year-old Harman won his second PGA Tour event in May and insists the pressure of leading the US Open will not faze him, despite having missed the cut in five of the seven majors he has played.
"I've got my wife and family here with me so I'll spend some time with them tonight and I'll sleep like a baby," said Harman, a former US Junior Amateur champion whose best major finish was tied 26th at the 2014 British Open.
World No. 33 Fleetwood has only made the cut once in his previous seven majors, but 22-ranked Koepka has knocked on the door with four top 10s including fourth in the 2014 US Open.
Asked what winning would mean, Fleetwood replied: "Well, it would change my life, I know that."
First-round leader Rickie Fowler, who is sharing a house this week with Thomas, recovered from a mid-round stumble with three birdies from the 14th to climb back to 10 under, one ahead of South Korea's Si Woo Kim, the Players champion.
Fowler, a four-time PGA Tour winner, has had two runner-up spots in majors among six tops 10s and is arguably the best of the current crop of young players not to have won a major.
"It's going to be a really cool day for someone tomorrow," said the 28-year-old, who finished in the top five in all four majors in 2015.
"I'm looking forward to my shot at it. I've been there a handful of times and had some good finishes. But I'm looking forward to getting the job done."
Patrick Reed, the man dubbed "Captain America" for his inspirational Ryder Cup performances, was on course for something special, too.
But two tame pars to finish left the world No. 19 becalmed on 65 for eight under alongside Russell Henley and Charley Hoffman.
England's Paul Casey, the co-leader at halfway, had a day to forget with a 75 to slip back to four under with Masters champion Sergio Garcia.
World No. 5 Jordan Spieth, who won the Masters and US Open in 2015, ended five over.
The last six majors have been clinched by a first-time winner, and with Garcia and former British Open champion Louis Oosthuizen the highest-placed major titleists at tied 17th, that streak looks set to continue.