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Bryson DeChambeau is leaking shots in the closing holes of his opening round. Two bogeys in a row now for the defending champion.

Playing partner Xander Schauffele makes a tidy putt for par on 16 to keep himself at four over, eight behind leader JJ Spaun.

As much as that looks a large advantage, Oakmont is a stiff test for all players and putting four solid rounds of golf together will be no easy task.

It's almost two years since Brian Harman won the Open at Hoylake and the American left-hander is quietly keeping in touch with the leaders at Oakmont.

Two birdies, two bogeys and nine pars in his first 13 holes.

He's had to play out sideways from the fairway rough on the fifth though, so maybe a bogey incoming...

Ouch! Rory McIlroy has a tiddler for par on the sixth but he hammers it through any break and it steams past the hole as he drops another shot and falls over par.

Given how hard players have to work around Oakmont to get any sort of joy, missing putts like that is a body blow.

Mexico's Alvaro Ortiz has five bogeys to his name today with just one birdie but he reduced the damage to his scorecard with a wonderful eagle on the 17th after driving to eight feet.

The 29-year-old is playing in the US Open for only the second time after failing to make the cut at Torrey Pines in 2021.

JJ Spaun is showing he's made of stern stuff.

He's saved par from tricky spots on numerous occasions today and he does it again on the eighth, two-putting from about 50 feet. The first putt wasn't the best but the second from just inside 10 feet was nerveless.

Just one more hole to go before the American can have a cup of tea and a sit down to reflect on a job well done - and also see how the day's late starters fare around Oakmont.

Another hole ticked off for Bob MacIntyre, who finds the 13th green but then watches his ball skip onto the top of the bunker into the semi-rough.

A lovely clip into two feet ensures he walks off with a par.

Defending champion Bryson DeChambeau goes in the bunker off the tee on 15 and ends up making a bogey five.

After making par on the seventh, US Open leader JJ Spaun lands his tee shot close to the flag on the long par-three eighth.

He ends up a long way past the pin but at least he's on the green.

Ludvig Aberg has just slipped into reverse gear here as Oakmont starts to get the better of the Swede, as back-to-back bogeys drop him back to level par for the day.

He won't want to finish any worse than this and could just do with steadying the ship.

A nice settler for Rory McIlroy on the fifth with a regulation par that's relatively stress free.

Shane Lowry is feeling the stress though as he sees a great birdie chance slide by the left edge of the hole - that was a bad read from Lowry as he struck his putt true enough.

One bogey brings two for Gary Woodland, who is now back at one under par after seeing his trickled par putt on 13 drift wide of the cup.

A couple of lusty blows sees Bob MacIntyre almost reach the green on the 618-yard par-five 12th. His ball snags in the rough just short and left though and he's left himself with a nasty chop on to a green that is running away from him.

He stabs his ball a couple of yards in front of him and this is looking decent but the ball wanders past the hole and keeps on shifting, eight, nine, 10, 11 feet... wow.

But the Scot knocks in the birdie try coming back and he's back to level. Tidy round.

Bryson DeChambeau looks on a little quizzically as a 15-footer for birdie on the 14th rolls by.

The par will keep him at one over, five shots off the lead.

Justin Rose has hit nine out of 13 greens today which is just outside the top 10 in the field stats-wise, and yet he's four over and it's clear to see why - the putter.

Rose is -3.95 in strokes gained putting which is second worst in the field, in other words his flat stick is stone cold and costing him any chance so far.

Can he heat it up somehow?

Phil Mickelson started brightly, reaching the halfway point of his round in level par, but has gone bogey, bogey, double bogey through holes one to three and is now four over for his round.

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You know what, that's an incredible six from Rory McIlroy as he rolls in a 30-footer to save his bogey on the fourth after an absolute calamity for most of the hole.

He's saved at least one shot there and maybe a couple given that a three-putt from 30 feet is not uncommon at Oakmont, so ironically after hacking around for most of that hole he'll walk off pretty happy.

Funny old game isn't it?

Xander Schauffele found the centre of the green with his tee shot on the par-three 13th but the American three-putts from about 35 feet and drops back to four over.

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Another excellent par save by JJ Spaun after finding the greenside bunker on the par-three sixth.

Just three more holes left today for Spaun, who now has a two-shot lead.

A first bogey of the day for Gary Woodland on the par-five 12th, unable to recover from finding the rough from the tee.

A bogey for Ludvig Aberg on the fifth and he slips back to one under alongside playing partner Adam Scott.

Still there or thereabouts though and anything under par will do just nicely today.