A solidly played first hole by Im Sung-jae.

His approach sticks on the front of the green, leaving him a long birdie putt, but he judges the pace pretty well and knocks in a five-footer for par.

Image source, USGA

My word, some of today's flags are clinging on to the edges of these massive, sloping greens at Oakmont. These are not easy folks...

Brooks Koepka immediately makes amends for that opening bogey with a birdie three on the 11th. He's back to where he started the day.

Image source, Getty Images

Patrick Reed picked up three shots on one hole thanks to his albatross, but he finished three over thanks to a triple bogey at the last - which clearly ruined his mood:

"There's 71 other holes we have to play. One hole doesn't mean jack, to be honest with you," said a fuming Reed after his round.

Asked to decribe that amazing albatross, he merely said: "It was a 3-wood I hit from 287, and it went in."

Having to then remind a reporter than he was three over and not level par did not help Reed's mood either....

It was tough out there yesterday, especially in the morning which actually played tougher than the afternoon - that rarely happens in the US Open.

And that's with the course a touch soft from recent rain and no wind...

The world number one tees off for his second round, looking for a lot better than the stuff he served up yesterday.

Viktor Hovland played pretty nicely apart from on the putting greens - as he ranked 147th in strokes gained putting, which when you think about him ending just one over is some effort...

The three former champions all fail to find the fairway from the first tee.

Jon Rahm goes into the greenside rough in two and his chipped third is some way from the cup. A bogey to start for the Spaniard.

Jordan Spieth and Dustin Johnson recover to some extent, giving themselves looks at par putts, but Spieth is the only man to walk off the first hole with a four.

Brooks Koepka is out from the 10th tee and his mood may well be darkening after an opening drive into the rough leads to an early bogey.

The American really got on a roll after his round yesterday, talking about the ticking off he got from his coach Pete Cowen on the eve of the tournament.

"I don't like having 'yes' people around me," said the five-time major winner.

"I just want somebody to tell me the truth. If I start swaying from being Brooks Koepka, then I want someone to call me out on it, and Pete did a helluva job on it.

"Justin Thomas thought he had to come check on me in the bunker. We were in there for about 45 minutes, and he was on the other side of the green.

"He was like, I was worried; your head was down. [What] Pete [said] I'll keep that between us. I wasn't happy with it, but it was something I think you need to hear or I needed to hear at the right time. It's not the first time he's done it. He's not afraid to."

Image source, Getty Images

Five-time major champion Brooks Koepka's team will be delighted to see him in the mix again, after missing the cut in the past two majors for the first time since the very first two of his career really got to him.

And it sounds like his bad mood was difficult to deal with..

"I would say from the first weekend in April until about last week, you didn't want to be around me," said Koepka. "It drove me nuts. It ate at me. I haven't been happy. It's been very irritating.

"It's a lot - I mean, I had to apologise - I've apologised to Rick, Pete, Jeff, Blake, my wife, my son, everybody. I wouldn't have wanted to be around me."

Image source, Getty Images

JJ Spaun held the lead for most of day one, other than a short spell when Im Sung-jae got to five under par after 11 holes.

There was a mini-collapse late in his round, with three bogeys in his final seven holes, but the man from South Korea ended two off the lead at two under par.

England's Tyrrell Hatton starts his second round at three over par - which is that "betwixt and between" position on the current leaderboard. He's just inside the top 50 and, with the top 60 and ties making the cut, a solid second round should see him through to the weekend.

Not a lot of huge household names in the top 10 bar Jon Rahm and Brooks Koepka, but all of these deserve all the credit for navigating Oakmont under par - they're the only 10 in the entire field to do so.

It was an unusually ragged first round from Scottie Scheffler, who leads for strokes gained in most metrics on the PGA Tour.

Yesterday, the best he averaged was 30th off the tee.

Expect these numbers to improve. Starting today.

Brooks Koepka showed glimpses of the form that carried him to two successive US Open titles in 2017 and 2018 on a first day that was more chastening for his playing partners.

Min Woo Lee and Justin Thomas need to be shooting no worse than a level-par 70 or maybe a 71 to make it through to the weekend.

For Brooks, his sights will be set on hunting down round one leader JJ Spaun.

Can Scottie Scheffler put himself back in the mix today?

The world number one is competing in his 24th major championship and his score relative to par of three over on Thursday was his worst opening round ever in a major.

Scheffler has also never come back from outside the top 30 at the end of the first round to win a PGA Tour event.

"The green speeds I think as the day goes on actually slow up, so the greens I think will be faster in the morning, but they should be a little bit softer. So maybe it'll be a little bit more opportunity to attack some of these pin locations," he said on Thursday evening.

"The golf course also plays longer in the morning, so there's challenges to it no matter what, and it's up to us to go out there and - I think tomorrow, when I look back at my round today, I think I just need to give myself some more looks at birdie.

"That's really all it came down to. I'll clean up some of those mistakes, a couple three-putts and stuff like that, and I think tomorrow will be a better day."

It all started so well for Rory McIlroy but he had a horror back nine including this double bogey.

Image source, Getty Images

Jon Rahm was as steady as steady can be in round one - he was one over after 11 holes (one bogey and 10 pars), before a birdie on the third and an eagle on the par-five fourth stuck him right into the mix.

That helped the Spaniard to a one-under-par round of 69, which means he starts today three shots off the lead.

He's in a group with two other former US Open champions. Jordan Spieth impressed in his level-par 70, while Dustin Johnson - winner when it was last staged at Oakmont in 2016 - ended five over.

Oakmont showed its teeth during the first round with just two holes offering scores under par.

Best cash in on the fourth and 17th folks - as every other hole is a minefield.

You just don't see that many around, so it's always exciting to get an albatross - especially in a major championship.

Watch Patrick Reed score just the fourth ever in US Open history yesterday, not that he knew too much about it at the time!

Just looking at the past three years, it is clear Oakmont provided a sterner test than either Pinehurst or LA Country Club.

The pros say to avoid double bogeys at all costs - well, there were more doubles in this corner of Pennsylvania on day one than in the first rounds of the past two US Opens put together.

And it's going to get harder on Friday!

Some big names are getting under way shortly.

Starting from hole one (all times BST)

12:29 Dustin Johnson (US), Jon Rahm (Spa), Jordan Spieth (US)

12:40 Tyrrell Hatton (Eng), Sung-Jae Im (Kor), Sepp Straka (Aut)

Starting from hole 10

12:18 Brooks Koepka (US), Min-Woo Lee (Aus), Justin Thomas (US)

12:40 Viktor Hovland (Nor), Collin Morikawa (US), Scottie Scheffler (US)

All Friday's tee times