Iain Carter
BBC golf correspondent on Radio 5 live sports extra

"Stunning. Absolutely stunning and it's that capacity to seize the moment that nobody else has. What a talent Spieth is at the top of the game."

Image source, Reuters

Branden Grace's bogey putt droops its legs over the edge of the hole, but stubbornly sits on the edge.

He started the hole level with Spieth. Grace has finished it three shots adrift.

The rest of the field have a runaway train to haul back in now. Spieth leads all of them by three.

Iain Carter
BBC golf correspondent on Radio 5 live

Is that the putt that gives Jordan Spieth back-to-back major titles? We've talked about Rory McIlroy keeping pace with Tiger Woods in winning majors but now Spieth is keeping pace with Rory.

Finally something drops for Jordan Spieth and what a time for his luck to turn!

I say luck, it was a perfectly calibrated putt. The line and pace making it irresistible for the hole.

He moves to six under.

And Branden Grace has a tricky putt just to make bogey.

Jordan Spieth has got a lucky lie. His ball is sat up pretty on a tuft of green just in front of a sprinkler head. Probably for the first time this week, he gets a bit of grip on a green. He could have done with some run and he has a good 12 feet to make a birdie that might put him out of sight.

Ian Poulter finished +11 for the tournament with a seven over par round today. The Englishman has posted some very strong words on Instagram and a photograph of the Chambers Bay putting surface.

Image source, Ian Poulter Instagram

He said: "This was the surface we had to putt on. It is disgraceful that the USGA hasn't apologised about the greens they simply have said 'we are thrilled with the course condition this week'."

"It wasn't a bad golf course, In fact it played well and was playable. What wasn't playable were the green surfaces. If this was a regular PGA Tour event lots of players would have withdrawn and gone home, but players won't do that for a major.

"They were simply the worst, most disgraceful surface I have ever seen on any tour in all the years I have played. The US Open deserves better than that."

Jay Townsend
Former American professional golfer on BBC Radio 5 live

I'm in disbelief of the shot I've just seen from Branden Grace.

Suddenly the mental floodgates open for Branden Grace and the pressure comes swarming all over his swing.

He cranks a horrible tee shot off right from the 16th. A hop along the tarmac road lining that side of the fairway and the ball comes to rest against the wire fence that separates the train tracks from the golf course.

That is out of bounds. The South African takes another off the tee. A decent punt, but he is three to there and is going to ship at least one shot.

Jordan Spieth is safe and sound by the way, just clinging on above a bunker.

Image source, AP

Louis Oosthuizen's finds the heart of the hole with his birdie putt on 16. That is his fifth birdie on the spin.

The force is strong in this one right now.

Three under and two holes to play.

Louis Oosthuizen's long, long eagle putt rolls up to within six feet on 16. He has a chance to pick up another stroke here.

Jordan Spieth makes a nervy par on 15, punching the air after a twitchy three-footer. I've got a nasty feeling he is going to miss one of those tiddlers before we are through. And it could be expensive.

Image source, Getty Images

Jordan Spieth makes a decent attempt to pull a birdie out of the hat from that tough bounce on 15. His curling snaking put rolls just by after setting off on a journey that Frodo would be proud of.

Dustin Johnson makes par at 14. He needs a bit of stability to rehab his game before trying to reel in Grace and Spieth.

Louis Oosthuizen hammers a very tasty tee shot slap bang down the middle on 16.

The South African, two under as it stands, is red hot.

Image source, Getty Images

Jordan Spieth is a wronged man.

His tee-shot at the par-three 15th lands within six feet, but rolls away to 25 feet distant from the pin.

The 21-year-old takes an angry swipe at the grass and pulls his fingers a foot apart to demonstrate how close he believes the ball would have ended up had there been any justice.

A bit of an exaggeration, but you take his point.

-5 B Grace (SA) 14, J Spieth (UA) 13, -3 D Johnson (US) 13, Adam Scott (Aus) F, -2 Louis Oosthuizen (SA) 15.

For a full leaderboard, click this way, external.

Louis Oosthuizen's sprint finish down the home straight continues with a birdie on 15. That is his fourth successive birdie.

And it moves him to two under.

The 18th is worth at least another shot to a man in form. It gets you wondering...

Iain Carter
BBC golf correspondent on Radio 5 live sports extra

"All of a sudden the hole looks the size of a thimble rather than a bucket for Dustin Johnson."

Image source, Getty Images

Jordan Spieth stands over a birdie putt on 14, but that looked like a misread to me. The ball screwed right after being set off on a pretty straight line.

Branden Grace pops in his par putt.

Spieth has a tendency to get a little yippy over the short range stuff and he takes a couple of looks at his two-footer before finally stepping up and draining it.

I think having a dead-straight one just threw him a bit.

And Jason Day's challenge can be packed away for the year and put down as another near miss at the US Open.

A double bogey six at 13 shunts him back down among the pack on level par.

Image source, Getty Images

Dustin Johnson is in a tailspin here.

He is suddenly putting like a man who has been introduced to the game for the first time this morning. Tone-deaf prods at the hole and he picks up another bogey and slip to three under.

Branden Grace and Jordan Spieth are still following each other around.

Their second shots at 14 land within a dustbin lid of each other but the whimsy of Chambers Bay decides that the ball should end up ten feet apart with Spieth the man left closer to the flag.