Collin Morikawa has a huge smile on his face as his 40-foot putt for birdie takes a bobble and then a few revolutions later almost bounces into the cup for his back-to-back birdies.

Jason Day looks a lot less jovial as he records his fifth consecutive bogey.

Not even Bryson DeChambeau can reach the 620-yard par-five 16th in two shots. His third ends up in the juicy stuff to the left of the green and he executes a 7/10 chip, knocking his ball down to around six feet.

Matt Fitzpatrick rattles in an 18-footer for a birdie, before Bryson lines up his par putt. Pulled it. Bogey.

Viktor Hovland nudges in from two feet to end his bogey run.

Image source, Getty Images

A couple of interesting little nuggets from today's round concerning the world's top two players.

Including today's round, world number one Scottie Scheffler has failed to break par in any of his last 10 US Open rounds dating back to the final round in 2023 at Los Angeles Country Club. He is 14-over during this stretch.

And Rory McIlroy's eagle at the fifth earlier was the fourth of his US Open career - and first since 2017 - but his first on a par-five at the 140th attempt. All three of his previous eagles were on par-fours.

A slightly overcooked chip from the edge of the green by Xander Schauffele leaves him a lengthy birdie putt at five.

He can't convert from 22 foot but cosies it up to the hole and cards a par.

A welcome birdie for playing partner Justin Thomas stops the rot of three straight bogeys.

Coming off a bogey, Aaron Rai has reached the 620-yard par five 16th, but after two decent digs, he tugs his third into the bunker.

A thump out of the sand leaves him a six-footer for par...and he makes it! Avoids back-to-back bogeys. Big.

2020 champion Collin Morikawa dunks a 25-footer for birdie to move back to level, but it's a six for Jason Day and his freefall continues apace.

Ryder Cowan hits the turn at three under.

He is only the fourth amateur since 2000 to shoot 32 or lower on their opening nine holes at the US Open, joining Omar Morales (2023), Davis Thompson (2020), and Brian Campbell (2015).

There's still a long way to go mind in terms of having thoughts of leading.

The last amateur to lead at the conclusion of any US Open round was Mike Reid and that was at the end of the first round in 1976.

Ah no, Bob MacIntyre.

Double bogey for the Scot. His tee shot found the rough and he never really recovered.

Just a bit of a momentum stuffer for Bryson DeChambeau on the 15th and it comes from the two areas that've plagued him this year - as he firstly misses the green to the right despite being in decent shape on the fairway.

Then it's another average chip that leaves him with a 15 footer, with a strong left-to-right break, to save par. And his effort just glides across the face and stays up - leading to his first bogey of the day.

Matt Fitzpatrick makes par but it's a fourth straight bogey for Viktor Hovland who just hasn't got to grips with the task at hand at all so far today.

Delicious from Jon Rahm. A snazzy chip lands right beside the hole. He is looking very confident.

Justin Rose sinks a mega 28-footer for birdie, while Jordan Spieth knocks it in from six feet for par.

Good golf all round.

Gavin Andrews
BBC Sport NI at Shinnecock Hills

Take into account a two hour delay for fog this morning and then a five-hour long slog around Shinnecock you’d think the world number one might want to get the feet up, but no. Scottie’s out hitting balls.

Ominous signs for the rest of the field!

Image source, Getty Images

Ah, Aaron Rai comes unstuck at the par-four 15th.

Another missed fairway means a chop out. He manages to land in between two of the six bunkers that guard this green, and while he chips up to eight feet, his putt doesn't drop.

Back to one under.

Jason Day's woes show no signs of abating, by the way. Another bogey for the Australian and he slides to four over. Needs to stop the bleeding.

Shane Lowry misses a putt from 13 feet for par. The Irishman is back to level par.

Jordan Spieth sprays his approach shot wide of the green, while Jon Rahm fares better but also is off the green.

Justin Rose finds the green and has a 44-footer for birdie.

Spieth chips up to gimme range, before Rahm goes one better, draining a 25-footer for birdie.

Rose tidies up for par.

Image source, Getty Images

The fourth hole is the hardest on the course?

Not for Xander Schauffele.

A peal of an approach sets up the two-time major champ with a 22-foot birdie putt to join the leader.

It doesn't drop but a tricky hole skilfully navigated.

We're seeing plenty of birdies so far in this late wave in brighter conditions - a far cry from the low cloud that blighted the course for those out early.

So, are they taming Shinnecock?

What do you reckon the winner will shoot?

Ryder Cowan is the new leader. The 21-year-old University of Oklahoma student drains a 15-foot putt on the 17th green to knock in his third birdie of the round.

This is some start from the US amateur.

Bryson DeChambeau has a great chance to take the solo lead on the 14th but he leaves his birdie putt just short when it was bang on line!

It's a 523-yard par four but that's no problem for DeChambeau, who rips a drive 339 yards and then sticks his second shot to 11 feet - and you fully expect him to roll it in for a hat-trick of birdies.

But he's just a bit too tentative with his effort as a big chance goes begging.

Image source, Getty Images

Ludvig Aberg was pleased with his opening round of 69: " Before the round started, if you would have said under par, I would have said, yes, and nodded.

"It's a challenging golf course. The wind is definitely a big, big factor. Overall pleased with the way I was hitting it and pleased with the way I was scrambling when I had to. It's a tough test."

On Shinnecock Hills: "It's such a cool place. Massive property, quite generous fairways, which today maybe didn't feel as generous with the wind, and obviously the green complexes stand out in terms of the challenges it presents.

"It's a very, very cool place to play golf at."

Despite missing the fairway at 14, Aaron Rai saves par after a stellar bunker shot from the trap short right of the green and keeps his early momentum intact.

I'd also like to draw your attention to the latest in a long list of bold sartorial choices from Jason Day.

What do you make of those trousers? He's three over already though so they may be binned after today's round.

Image source, Getty Images