One shot back at seven under are Justin Thomas (14), Marc Leishman (10), Brendan Steele (10), Hideki Matsuyama (9), Xander Schauffele (7) and Rickie Fowler (6).
The 2009 British Open victor made his first appearance at the U.S. Open in three years, having secured a qualifying spot at the Columbus, Ohio, sectional.
Harman closed with two birdies and three tough pars for a 5-under 67 that gave him a one-shot lead at 12-under 204.
"I did everything I could to make more birdies coming in", he said.
Thomas finished in style, and it had nothing to do with his hot pink trousers.
On the final hole, a 667-yard par 5, Thomas hit a 3 wood (!) off the tee that travelled some 350 yards, leaving himself 310 yards to the pin, with a slight following wind.
"I'd like to shoot a good round here, you know, I'm on the verge of it I feel like", Stricker said.
Zach Johnson holed an 8-foot putt on the par-3 ninth for his third birdie of the front nine.
Thomas leads the U.S. Open after shooting a 63 in the third round, matching the major record for low score.
"The finish was awesome".
It is the 31st time a 63 has been recorded at the four big dances, with Greg Norman and Vijay Singh the only golfers to do it twice. "It means I have a lot better chance to win the tournament than I did when the day started".
"A little disappointing to end with the double on 17 but I started hitting it a lot better on the back side", Hadwin said minutes after his round.
"I think since my dad dropped me off at football practice and told me to not be disappointed if I didn't get to play at all", Harman said, drawing laughs. With a blind shot to the green, he went long into deeper hay, and his first hack at it moved the ball only a few feet.
Thomas set the U.S. Open scoring record despite registering a pair of bogeys, offsetting them with nine birdies and his closing eagle.
Thomas was tied for 24th at two under par, five strokes off the pace after Friday's second round. He was 10 under.
"It's going to be a really cool day for someone tomorrow", Fowler said.
"I was upset with the score I had made, but it did not have any effect on my attitude or how I was going to then approach the rest of the round or the next shot. When I get it going, I don't fear it like I used to of stalling".
Fleetwood and South Korea's Si Woo Kim are the only non-Americans in the top 13.
Johnson shot 1-over 73 on Friday to finish at 4 over, three shots off the cut line.
Provided the rain stays away, Brandt Snedeker believes the course will get dry and fast enough to create a little more separation. He's only two shots behind Champ, still with a chance of joining Crenshaw, Leonard and Spieth as Longhorn U.S. Open low-am medalists. Thomas rolled in an 18-footer that went right to left from the edge of the green.
The USGA has a history of pushing the envelope when setting up courses for the USA championship.
"So, I am a pretty happy man".
But the work is not done. "It will be a pleasure to go out on a Sunday trying to win a major".
At least 30 confirmed dead following London tower fire
The cause of the Grenfell Tower fire is still unclear, but residents have been claiming since 2009 that the building was unsafe. A lawyer for the family told CNN that Trevisan spoke with her parents before she died, telling them: "I am going to heaven".
India vs Pakistan cricket rivalry
Malik has had a quiet tournament by his standards but I expect him to come good on the big occasion. Some teams start confidently and then they fade.
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Families searching for their loved ones have blanketed the area near the tower with posters in a desperate search for information. Residents' voices must be heard in the public inquiry and funds will be made available for their legal representation.
Dustin Johnson misses cut at US Open — Major Surprise
On No. 7 he sank a 15-footer. "But more important than that was just to get myself in contention to win the tournament". He said that his 16 years of experience is what allowed him to keep the wheels from falling off on the par-5 14th hole.