Matt Fitzpatrick, winner of this championship in 2022, is off to a terrific start, nailing a 25-footer across the first green to move immediately into the red.

A nerve-settler if ever I saw one.

Stephen Watson
BBC Sport Northern Ireland at Oakmont

It’s not the length of the rough but the density which seems to be the biggest challenge at Oakmont.

The US Open is renowned for penal, long rough but this is some of the most brutal ever seen.

Rory McIlroy joked to reporters that he’s glad there are spotters to find balls this week.

US Ryder Cup captain Keegan Bradley enjoyed a wonderful US PGA Championship last month, eventually finishing in a tie for eighth spot.

A slightly wayward approach to the first green is punished and he drops a shot on the opening hole, but he gets that straight back with a birdie on the second.

Brian McLauchlin
BBC Scotland

It's 26 years since a Scot won a major, but Colin Montgomerie says Bob MacIntyre has the game to end that run.

MacIntyre is currently ranked 20th in the world and has won two PGA Tour events, but has yet to make a significant impression in a major.

“He's there to win and he's good enough to if it all goes his way," former European Ryder Cup captain Montgomerie told BBC Scotland. "We haven't said that about a Scottish golfer for a long time."

England's Jordan Smith taps in a short birdie putt on the 618-yard par-five 12th to get back to level par.

Smith, who came through a qualifier at Walton Heath last month, is playing in his third US Open, having finished joint 20th in 2023.

He was green-high in the deep cabbage after two shots on the 12th and played a delightful chip out to three-feet to set up his birdie.

Image source, Getty Images

Rory McIlroy leaves himself nine feet for birdie on the 10th, his first hole today, after a lovely approach, but he can't find the cup so has to settle for an opening four.

Justin Rose gets down in two from 40 feet away for his four and Shane Lowry does similar to make it pars all round.

That's a chance miss for McIlroy though - and in the US Open you have to grab those with both hands as they can be few and far between.

Ludvig Aberg is some player. This is just his second US Open but like everything else the world of major championship golf has to throw at him he's taking it in his stride.

In total control of his golf ball so far he adds a birdie at 11 to his opener at 10 and he's two under after two. That's how to start the US Open.

Nice easy one to start...ahem.

The par-four first hole played as the most difficult hole, statistically, at the 2016 US Open with the field playing it in a combined 200 over par.

There were 33 double bogeys or worse nine years ago, the highest total for any hole.

Get on social media though to watch players having fun on the practice days this week, using a putter from 120-150 yards short of the green.

Bryson DeChambeau's approach lands right up against the fringe on the first green and his birdie putt from about 20 feet sails almost 10 feet past the hole.

The par attempt slides past the right edge and it's a bogey to open up for our defending champion.

An uneventful, safe par for Xander Schauffele, who judges the break on a 30-foot birdie putt pretty well to leave a tap-in for a four.

England's Tommy Fleetwood has long been talked about as having the game to win this championship and he went close in 2018 at Shinnecock Hills, finishing runner-up to Brooks Koepka by one shot after a closing round of 63.

Anyway, the Englishman is off to a slightly wayward start and has to take a penalty drop after finding a ditch off the tee on the first hole. But he nails a 10-footer to only drop one shot and that will make him feel a whole lot better.You're going to make plenty of bogeys this week, just don't turn them into doubles.

This European Ryder Cup trio of Rory McIlroy, Shane Lowry and Justin Rose get their US Open campaigns up and running.

McIlroy has finished second in the past two years and has six straight top-10s in this event, which is a simply stunning return given how tough it is.

Rose is a former US Open winner and Lowry held a four-shot lead going into the final round the last time the tournament was played here at Oakmont.

Image source, Getty Images

Xander Schauffele has an incredible US Open record - he's played in the event six times and has finished no lower than 14th, as his record reads: T3-5-T7-T14-T10-T7.

And his secret is perhaps his attitude to this toughest test in golf, which is to embrace the chaos and rise to the challenge.

"I don't know, maybe I'm just sick and enjoy the challenge," he said. "Something about it playing really hard.

"I think a good attitude goes a long way. It's obviously easier said than done, hard to keep a good attitude through the entire stretch of 72 holes, nonetheless practice rounds as well.

"I don't know, I think they're a lot of fun."

Ludvig Aberg is known for making fast starts in the majors, and he's made another with a brilliant birdie on the 10th - his first hole of the day.

Oakmont is tough, but it does give you chances if you can find fairways and greens, which the Swede does superbly well to leave a nice six footer that he rolled in for a three.

Bryson DeChambeau begins his quest for a third US Open title alongside world number three Xander Schauffele and last year's US Amateur champion Jose Luis Ballester.

DeChambeau has been a regular contender for golf's biggest prizes in recent times, finishing in the top six in five of the past six majors.

Dressed in a bright red polo shirt and white trousers, DeChambeau sends his tee shot into the rough on the left of the fairway.

Image source, Getty Images

Oakmont Country Club is far from new to holding golf's grandest tournaments.

This year the Pennsylvania course which is widely regarded as one of the toughest and greatest tracks in the United States, is hosting the US Open for a record 10th time, having previously held it in 1927, 1935, 1953, 1962, 1973, 1983, 1994, 2007 and 2016.

In addition, it has hosted three PGA Championships (1922, 1951 and 1978), two US Women’s Opens and six US Amateurs.

Image source, Getty Images

Rory McIlroy achieved his lifelong dream at The Masters when he completed the career Grand Slam, so you can forgive him for struggling to find a reason to put in all the hard grind needed to stay on top of his game.

And ahead of the US Open he admitted that he's still celebrating his Augusta National triumph and is just finding it a bit tough to get his focus back.

"You dream about the final putt going in at the Masters, but you don't think about what comes next," said McIlroy.

"I think I've always been a player that struggles to play after a big event, after I win whatever tournament.

"I think chasing a certain goal for the better part of a decade and a half, I think I'm allowed a little bit of time to relax a little bit. But here at Oakmont, I certainly can't relax this week."

Image source, Getty Images

What a way to start!

American qualifier Maxwell Moldovan has holed his second shot from 189 yards on the par-four first and is immediately out into the lead at two under.

He landed his ball short of the green and it hopped on and then trickled ever so slowly into the heart of the cup. Moldovan couldn't see it go in the hole from where he hit the ball, and was somewhat surprised to hear loud cheers from those assembled round the green.

Could Shane Lowry be in contention this weekend?

The Irishman has had four top-10 finishes this season on the PGA Tour and shown the sort of form that suggests he is ready to land another major after winning the Open Championship in 2019.

However, he recently told the Irish Times, external he feels like he has come of the course every Sunday after being "punched in the gut" because he is not getting the rewards for his play.

Here he chats to BBC Sport NI about his season so far and his hopes of winning some more silverware ahead of the US Open at Oakmont, a course he came close to triumphing at in 2016.

Image source, Getty Images

Jason Day is golf's great fashionista - in a way. Here's two of his looks for the practice rounds - going from the Rocky Balboa all American shorts to what looks like a full-on Wimbledon tennis outfit.

Thumbs up or down for these outfits?

Stephen Watson
BBC Sport Northern Ireland at Oakmont

Rory McIlroy spent Tuesday and Wednesday afternoons grinding on the range at Oakmont.

He’s also been working very hard early this morning with the help of one the world’s most exclusive launch monitors - the green trackman presented to him for winning the Masters.