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That excellent approach shot to the seventh earns Bryson DeChambeau a second birdie in three holes and he is under par for the first time in this tournament.

But it's a nightmare hole for Xander Schauffele, who finds a fairway bunker off the tee and then three-putts from the front of the green for a double-bogey six.

Next up for this group is that massive par-three eighth hole.

England's Jordan Smith is back to level par after a huge birdie putt on the first hole, his 10th.

His ball looks like it's going to miss on the high side but bends in at almost a 90-degree angle at the final knockings.

Denmark's Niklas Norgaard pours in a birdie on 13 to get to two under after just four holes as he makes a fast start at Oakmont.

The 33-year-old came through Final Qualifying to book his spot in the field at just his second major championship following his debut at the US PGA Championship last month.

The 17th is a driveable 327 yards today and Adam Scott takes advantage, powering his tee shot into the heart of the green.

The Aussie's radar is a little off with the flatstick though, racing his putt a good five feet past the hole. But he nails the return to get himself under par for the championship.

Ouch - Ludvig Aberg has a great chance of 17 with a short putt for birdie but he can't get it to drop and he stays on one under.

The Swede keeps his cool of course, but there's just an extra touch of sauce on his drive down 18, which he smacks miles and also finds just his third fairway of the day.

JJ Spaun's long birdie putt on the 18th pulls up short but a par will do very nicely indeed and the American has played the back nine of the golf course (his first nine holes today) in just 31 strokes.

Is Bryson DeChambeau starting to find his range?

An iron into the seventh green is right over the top of the flag and comes to rest about six feet from the hole.

Birdie chance incoming...

Nice par save from Rory McIlroy from just short of the 15th green as he makes sure he keeps a bogey off his clean card so far.

Justin Rose can't keep his card clean though as he makes a first bogey of the day - but it'd been coming as he's been scratching around a bit so far and doesn't look overly comfortable.

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Consecutive birdies on four and five have lifted Gary Woodland into second spot on his own, one behind leader JJ Spaun.

All three players in this group walk off the sixth hole with par threes on their scorecards.

Bryson DeChambeau chips from just off the green and almost into the hole, but will be happy enough with a par as his tee shot had landed in a pretty difficult spot.

Wowzers - JJ Spaun is now four under par after eight holes after sinking his 12-footer for birdie on the 17th.

If he can keep this sort of form going, he'll be posting a very tough target for the rest to try to match.

US Open debutant Cameron Tankersley has found out very quickly that any mistakes around Oakmont will be punished and punished badly.

His tee shot on the first goes right and it takes him a couple of goes to get back on the short grass, before eventually carding a triple-bogey seven.

A tough school.

Just nine of our early starters are currently under par for their opening rounds:

• -3 Spaun (7*)
• -2 Clark (4), Woodland (4), McIlroy (5*), SW Kim (4*)
• -1 Aberg (7*), Detry (3), Harman (3*), Norgaard (2*)

Matt Fitzpatrick has always struck me as the most mild-mannered of golfers but even he is letting fly with an expletive or two after dropping a shot on the par-five fourth.

The Englishman goes chasing the green with his second shot on the 618-yard hole but his ball gets snagged in the rough just short. It's in an awful position and he's got his feet in a bunker as he hacks out.

Zero control and the ball whizzes past the hole. Three more shots from there and the 2022 champion is stalking off the green, that early birdie a distant memory.

Xander Schauffele pays the price for missing the fifth fairway with the first bogey of his round and the man who won two of last year's four majors is back to level par.

He's joined on that score by Bryson DeChambeau, who sinks his seven-footer for a first birdie of the day.

Their playing partner Jose Luis Ballester stops his personal rot - after four straight bogeys, he pars the fifth.

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Phil Mickelson is playing in his 128th major championship at this week's US Open, which breaks his tie with Raymond Floyd and puts him in solo fifth place in the all-time list of appearances in men's majors.

He's still way behind leader Jack Nicklaus though and a few other greats of the game - but shows Mickelson's longevity at the very highest level of the game.

Most appearances in men's majors:

1. Jack Nicklaus - 164
2. Gary Player - 150
3. Tom Watson - 145
4. Arnold Palmer - 142
5. Phil Mickelson - 128

JJ Spaun is into the lead on his own thanks to a third birdie of his round on the par-three 16th - his seventh hole of the day.

Spaun's tee shot is a brilliant one, within eight feet, and the birdie putt drops.

Bryson DeChambeau is involved in a lengthy chat with a rules official after his second shot lands on a walkway across the fairway. His ball is picked up to take relief, then placed, then dropped... everyone seems a little bit confused as to what's happened.

Maybe the ball had been picked up to take relief but then he decided against it, but having not marked where his ball originally came to rest, he then was forced to drop it?

Anyway, it eventually concludes with DeChambeau sending his third shot into the heart of the green, and in the end it's a par for the American.

Meanwhile, Xander Schauffele can't sink his eagle putt but that wonderful approach does yield a birdie that takes him to one under par.

Tommy Fleetwood is edging back towards parity. He judges a left-to-righter to perfection, sliding in a birdie attempt from a dozen feet on the fifth.

Much better distance control by Robert MacIntyre on the par-four third hole, firing to the heart of the green from 150 yards. His ball tries to spin and stop on the putting surface but it catches a slope that trickles the ball off the back edge.

His ball is not in the thick stuff but he's chipping and, perhaps nervy of the pace of the greens, leaves his birdie effort five feet short. Good saver though and he escapes with par.