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Fleetwood duly pays for that poor chip on eight as he fails to make par and falls further behind.

Not looking good for the Englishman's chances. Needs a big momentum change and very quickly.

Jay Townsend
BBC Radio 5 live at Erin Hills

I got a chance to watch Koepka a bit in Europe. You could see he was super talented and he fought his way up the rankings to get on the PGA Tour. He's a super nice guy. You can see he carries himself with a lot of confidence but he doesn't offend people with it.

Oh you would most definitely rather be in Koepka's position.

The American steps up and sinks a 33ft putt to move to 14 under and seize the outright lead.

Imperious.

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Rickie Fowler navigates a shoulder in the ninth green well and that gives him par from a tricky spot. Kim Si-Woo has something similar and also sorts out two putts. These two chugging along. They need the afterburners...

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Here comes Hideki!

Matsuyama caps off an excellent second shot at 12 with a perfectly-judged putt to claim back-to-back birdies and move to 10 under.

Watch out above.

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The US Open of 1990 at Medinah gave up 28 below par scores. This number will be probably be beaten this week. Medinah has not hosted the tournament since.

Ernie Els believes Erin Hills should get it again and after today's round said the course would be playing at about two under for the winner had the wind been as it is today all week long.

As we stand, 31 men are under par.

You'd still much rather be in Koepka's position.

Fleetwood misjudges his chip and leaves himself a momentous par putt.

Slightly misjudged second shots from both Koepka and Fleetwood at eight.

Koepka goes short and just about keeps it on the green, while Fleetwood bangs it over the back.

Tough for both but you'd rather be in Koepka's position.

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Rickie Fowler walks from a solid par on eight and now hits a good looking iron into nine, a par three. "Mac and cheese", comes the shout from some pumped spectator. The ball lands within 15ft but that slope is going to take all the delight of a mac and cheese out of things as the ball rolls a good 30ft further back.

Fowler is going along nicely but our leaders are just gripping on with the strength of Max Whitlock. Brian Harman goes close for birdie on the seventh but only takes par from the par five.

As I mentioned earlier, holes eight to 13 are tricky. The leaders are starting that drag.

Chris Latchem
BBC Radio 5 live commentator at Erin Hills

A beautiful shot by Brian Harman on the par-five seventh and it snakes around to leave himself 10ft for a birdie and the outright lead.

You can listen to Chris and the team on BBC Radio 5 live now. Just click 'live coverage'.

Steve Stricker is lighting up the crowd here on his local territory. This is a man who braves the Wisconsin winters by hitting balls out of the back of a heated trailer and into the snow.

On the 17th he puts a birdie putt away to reach five under. Not bad at all for a man who first won a PGA Tour event in the mid over 20 years ago.

Matsuyama ends a quiet spell with a birdie on 11. Perhaps running out of holes to do real damage but one to keep an eye on.

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Well despite his travails in the fescue, Koepka does salvage the situation to even set up an outside chance of birdie.

He misses but he'll be delighted to make par from where he was after his tee shot.

Fleetwood has a long birdie chance down the hill - left it short but kept his cool to tick off another par.

American amateur Scottie Scheffler birdies the last to finish one under for the championship.

He was on course for a better score but made two bogeys and a double bogey on the back nine today.

He's currently level with Cameron Champ as the top-ranked amateur.

Champ has four holes to better Scheffler's mark.

Iain Carter
BBC golf correspondent at Erin Hills

What will be the winning score today? Do you prefer it when it's much more US Open-like and the players are having to grind for their par?

Or did you prefer it over the first three days and the spectacular scoring that we saw from Justin Thomas yesterday where there were more and more birdies?

Get in touch now on #bbcgolf.

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Rickie Fowler needs to get it going and the seventh green gives him a chance at birdie from range. This to milk a par five for all it's worth... crackerjack putt. Very much needed.

Justin Thomas, pretty in a pink t-shirt, also has to drain one from range but his is only close. Nothing for leaving it above ground dear boy.

As we've just told you, Brooks Koepka is scrambling, so can Brian Harman save par on the sixth from six feet. You bet.

That Fowler birdie looks good now.

It's not actually too bad a lie for Koepka on seven...but he's really failed to capitalise and has left himself a very awkward third shot, still 137 yards short of the hole.

First big error of the day from Koepka - can he scramble a par?

Jim Congleton: In Bangkok awake with jetlag & a workable but ropey internet connection. Thanks for the coverage.

You're welcome Jim. If we can live up to the chaos of Bangkok we will have done you proud.

John McLellan: Don't you think Brian Harman looks like Ricky Ponting? Love a sporting lookalike.

We did post this yesterday John and had people sending us their own lookalikes. We are with you, he looks very much like the Aussie.

Fleetwood did indeed do well to make 'just' a bogey at six. But he's now three shots behind his partner and co-leader Brian Harman.

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Golfing World sum up how rock solid Brooks Kopeka looks.

The American makes another easy par at six and onto seven...

Oh, Golfing World might have gone too early - Koepka's tee shot on seven is way left and deep into the rough stuff.

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