Evening all. You weren’t planning on going to bed, were you?

The real business is just getting underway at Chambers Bay as the 2015 US Open comes to what will most likely be a dramatic — and late — conclusion.

The final groups are all slated to tee off over the next 50 minutes which means that we should know our winner by about 3.30am Irish time.

Did we mention that we’re in for a late one?

It’s worth it though because there’s an Irishman in contention. Shane Lowry will start the evening in a tie for fifth, three shots off the lead which is currently shared by four men — Dustin Johnson, Jordan Spieth, Branden Grace and Jason Day.

If we’ve learned anything over the last few days, it’s that Chambers Bay is one hell of a unpredictable course. Lowry would need a lot of things to go in his favour, but if you’re not in, you can’t win.

Here are the tee times you need to know. Lowry, who is playing alongside JB Holmes, is in the next group out. He tees off in 11 or 12 minutes.

Phil O’Meara: If Lowry posts a couple of birdies in the first few holes I am going to be faced with a real dilemma! Totally worth it to have another member of the Irish major winner club. Here’s hoping.

You’re not the only one, Phil.

Some of the early scores on the course suggest that it will be possible to shoot a few under par out there today. Morgan Hoffman and Thomas Aiken both shot 66s earlier today while, as I type, Rory McIlroy has birdied the eighth.

That his third birdie of the day to move to +1. It’s likely to be too little, too late but it will give plenty of confidence to Lowry and others looking to reel in the leading quartet.

LOWRY TIME!

Holmes steps up first and drives straight down the middle of the first fairway.

“Hopefully he’s not too excited,” Paul McGinley says as Lowry steps up. It looks as if the adrenalin is surging though as he hooks his opening drive into the rubbish on the left. Hopefully he has a decent lie.

Martin Sinnott has been in touch via email. Here’s the slightly edited, PG version of what he had to say:

Watching the U.S. Open on sky sports 4 is impossible. It’s so frustrating. From 7 o’clock they keep showing the top 5 leaderboard even though they don’t go out till 11. For every hour there is 30min of adds and waffle. I’m giving up.

Thank God for liveblogs, eh?

Sport@the42.ie is the email address for anyone else with something to get off their chest. I’m here all night — literally here all night.

Decent second shot by Lowry to get it out of the garbage. It takes a couple of bounces and rolls down a couple of yards short of the fringe. The first is playing as a par four today so he’ll have an up and down from there.

Rory’s on the charge!

McIlroy is arguably playing the best golf of anyone out there at the moment. He’s just played a brilliant shot from the sand on 10… and rolls in the birdie putt! He’s now just four off the lead.

He couldn’t, could he?!

PAR FOR LOWRY

Nerveless stuff as Lowry rolls in the six-footer for par on the first. Confident recovery after his tee shot left him in a difficult position.

Caro has nailed her colours to the mast:

American hero Jordan Spieth has just sent his opening drive out into Lowry country — ie the garbage on the left.

Branden Grace, a man who has never managed a top-10 finish in 12 Major starts to date, is his playing partner today.

The second has been giving up a couple of birdies today and Lowry has played a nice approach to leave himself with a 10-footer. That’ll be his first chance of the day.

His playing partner JB Holmes made an absolute hames of the first, by the way, finishing with a double-bogey six to drop down the leaderboard.

Lowry starts that putt on a line to the right of the hole but it doesn’t quite turn for him and misses on the high side. Should be a tap-in from there for a par-par start.

Solid as a rock.

On the long 11th, Rory missed the green by a long way to the left but he’s saved himself with a beautiful chip on to within a couple of feet.

Chambers Bay’s crazy golf greens have caught Lowry out on the par-three third. He hits what would be a perfectly acceptable tee shot on any other course but it takes a hard bounce and wheels away down a ridge to the back left corner of the green. It does well to even stay on the green, in fact.

Dustin Johnson and Jason Day both find the first fairway with their opening drives. That’s everyone underway now. May the best man named Shane — or failing that, named Rory — win.

Anyone know where I could get myself a pair of these beauts?

Charlie Riedel Charlie Riedel

Spieth and Grace both miss their birdie putts at the first … and then Spieth misses his putt back! That’s a bad bogey to start.

BOGEY FOR LOWRY

That piece of misfortune has cost Shane Lowry his first shot of the day. He couldn’t get his first putt any closer than to within 10 feet, and then his par putt just tailed away to the right.

Disappointing but there’s a lot of golf to be played yet.

Day and Johnson — JD and DJ, if you will — both have birdie putts at the first but both have to settle for par.

Nobody making any early moves which must be music to Rory’s ears as he lines up an eagle putt at the short 12th.

BIRDIE FOR RORY!

Rory’s eagle putt leaves him with a very makeable birdie putt to go to five-under for the day and one-under for the tournament. He rolls it into the heart of the cup from five or so feet.

Chaaaaaaaaaaarge!

This would be the story to end all stories though. He started the day eight shots off the lead — now there’s only three in it!

Rory hits his 217-yard approach to the 13th right at the flag and it scoots on out the back of the green. Doesn’t look like he’ll be making any more ground here.

Lowry finds himself on the top shelf — good for whiskey, not so good for the fourth green at Chambers Bay. He tiddles his putt over the top of the ridge and watches as it picks up speed and rolls on by the hole. He couldn’t have done much better but he still has work to do for his par.

BIG SAVE FOR LOWRY

There was more to that putt than I thought at first look. It breaks from right to left but Lowry has the line and pace just right and it sneaks in the side door.

After dropping a shot on the third, that was crucial. He stays at level par, four off the lead.

RORY. RORY. RORY!

Remember when I said that Rory was unlikely to make up any ground after his approach to 13? He’s just rolled in a MONSTER birdie putt — and I don’t capitalise the word “monster” lightly.

You should hear the noise of the gallery! There can’t be too many players out there who didn’t hear it.

Rory is now six-under for the day, two-under for the tournament, and just TWO SHOTS BACK!

Bunker for Lowry on the fifth. He tries to go straight at the flag with his approach but it doesn’t quite have the legs and drops short into the sand that’s protecting the pin.

Rory’s at it again! Sensational approach into 14 and he’ll have a tiddler for a third straight birdie.

BOGEY FOR LOWRY

He pulls his par putt at the fifth and drops back to +1. It’s starting to unravel.

MCILROY MISSES

You’d put your house on him making the five-footer for birdie at 14 in the form he’s in but it just leaks away. That’s disappointing.

Here’s the current leaderboard. A word for Adam Scott who is powering through the field as well.

Here’s that monster McIlroy putt from earlier:

BOGEY FOR RORY

That’s his first of the day, and it’s really not the time to have it. That makeable birdie on the previous hole could have moved him to -3; instead, he’s back on -1 now and three off.

Not sure exactly what G-Mac is suggesting here but I could hazard a guess…

At least we know who to blame!

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BIRDIE FOR LOWRY

Lowry’s brilliant approach to six pays dividends and he rolls in his first birdie of the day to move back to evens, five shots behind Dustin Johnson who has edged into the lead.

And as Johnson birdied the fourth, Jason Day dropped a shot. DJ now holds a two-shot lead.

The wheels are starting to come off a bit for Rory. He has a straightforward chip on at 16 but gets it horribly wrong. That will most likely cost him his birdie chance — although you may remember what happened the last time I said that…

Par for Rory on 16. Still though, a birdie-birdie finish would put so many cats among so many pigeons.

So close for Johnson at the fifth but his birdie putt just falls away.

Day has a 13-footer of his own… and makes it! He’s back to four-under and DJ’s lead is cut to a single shot again.

BOGEY FOR LOWRY

The US TV execs appear to have given up hope on Shane Lowry. Away from their prying eyes, he’s bogeyed the seventh and dropped back to +1 again.

TV have found Shane Lowry again where he’s laid up on the par-five eighth. He stitches it and, barring disaster, he’ll birdie that and move back to level par.

BOGEY FOR MCILROY

That’s the worst bogey of the lot for McIlroy as he misses an easy one on the par-three 17th.

BIRDIE FOR LOWRY

No mistake – he’s back to EVS through eight.

BIG SAVE FOR DJ

Johnson looks a certainty to drop a shot at the par-four sixth but somehow manages to hole out for par. If he wins, that will be pointed to as one of the crucial moments of the round.

A check-in on American hero Jordan Spieth:

He appears to be giving himself birdie looks on practically every hole. So far today, he has made zero birdies.

BOGEY FOR LOWRY

He misses to the right on nine and drops back to +1 and a share of 11th place.

MCILROY SHOOTS 66 TO FINISH ON LEVEL PAR

It’s a par five at the last for Rory. For a brief moment about an hour ago, it looked like he could snatch this tournament in spectacular fashion. It didn’t quite work out but he certainly didn’t lose it on the basis of today’s play, that’s for sure.

Jason Day is falling away. He’s going to bogey the seventh and will be three shots behind Johnson.

Meanwhile on the eighth, Jordan Spieth makes his first birdie of the day and moves to within a shot of DJ.

BIRDIE FOR LOWRY

He’s had more ups and downs than a yo-yo in this final round. He reads the line brilliantly on 10, starting it left and watching as it breaks back across the face of the hole before dropping in off the right edge.

Back to level par again.

Here’s how the betting looks at 0.50am, if you’re curious:

They’re queuing up behind DJ! Branden Grace birdies the ninth and he joins Spieth on -4, a shot off the lead.

That’s BRANDEN Grace, not Brendan Grace.

Jason Day needed that! He birdies the eighth to move back to -3.

But there’s no mistake for Johnson so also makes birdie on the par-five and now leads on -6.

If you thought Jason Day was dead and buried after those bogeys at four, six and seven, you may have thought incorrectly.

He’s just played a peach of tee shot at the par-three ninth, catching the slope and letting it feed back down to the hole. He’ll have a golden opportunity to move to -4 and back to within two shots of Johnson.

Great opportunity for Lowry to dip back into the red numbers at 11. He gets a lucky break when his tee shot finds a cart path and his approach from all of 220+ yards is magnificent, coming off the slope at the back of the green to about seven or eight feet.

He has the line but hits the putt a little too firmly and it catches the right edge before staying out.

Lowry follows that up with a smashing tee shot at the short 12th. He’ll have a long putt for eagle but at worst, he’ll be hoping to two-putt for the birdie.

It really hasn’t been Jason’s Day and you get the feeling that his search for a first Major success will go on.

He bogeys 10 to drop back to -2. Johnson also drops a shot after a wayward approach and his lead is cut to one again.

Nothing — I mean, NOTHING — has dropped for Jordan Spieth today. He looks to have done everything right with his birdie putt at 11 but it misses by a fraction of an inch.

He’s had so many chances.

Lowry back into a tie for sixth

ADAM SCOTT POSTS CLUBHOUSE LEAD OF -3

A brilliant closing round of 64 for Scott and while it’s unlikely to be enough, he won’t be going anywhere just yet, you suspect.

AAAAGH!

Lowry has plenty of work to do for his par on 13 but his putt is practically perfect. It just stops a dimple short of dropping in.

Spieth judges his eagle putt on the 12th to perfection, leaving it about two feet away. We’re about to have co-leaders here as the back nine heats up!

BOGEY FOR JOHNSON – SPIETH & GRACE LEAD

How quickly things can change? Spieth and Grace make birdie at 12 to move to -5, Johnson bogeys the 11th.

One for you stats boffins: IF Jordan Spieth wins here, he will be the first player to win the Masters and US Open in the same year since Tiger in 2002.

Impressive.

Lowry hits his approach at 14 to 15 feet or so. He’ll still on level par; he would need to get to -2 for a top-five finish which would be just reward for an excellent week.

Dustin Johnson is making plenty of opportunities but he needs to start converting. He stands over a seven-footer for birdie at 12 but it misses on the low side. He remains a shot adrift of the leaders.

BIG putt from Grace to save par at 13. If you thought he’d slip away over the course of the evening — as, I’ll admit, I did — he’s certainly proved you wrong.

This is very worrying if you’ve backed Johnson:

Par for Lowry on the 14th. He’s tied for ninth at the moment which would equal his best Major performance.

Meanwhile on 13, Jason Day’s challenge looks to have very definitively met its end. He’ll be lucky to get away with anything better than a double-bogey six.

Up ahead of 14, Spieth and Grace are peppering the flags. These two could strike out on their own before long.

Par for Lowry on 15. His putt just didn’t quite have the legs, despite his best efforts to urge it on towards the hole.

BOGEY FOR JOHNSON

If you had the 13th hole in the sweep for inevitable Dustin Johnson implosion, come on down and collect your prize. It’s only a bogey — but now is not the time to be dropping silly shots.

All of a sudden, Spieth and Grace have a two-stroke lead. Grace has been remarkably consistent today and just parred 14. Spieth has a birdie putt of his own still to come…

Nope! Spieth never started it far enough to the left.

Louis Oosthuizen is trying to do a Charl Schwartzel and steal this with a string of birdies at the death. He’s birdied 12, 13, 14 and now 15 to move to -2.

He’s three back with three to play. Surely he couldn’t?

Jordan Spieth’s tee-shot at 15 looked good but as we’ve seen so often this week, if you’re a foot away from where you need to land, you can end up 50 feet away by the time the ball comes to a rest.

You don’t need to be a lip-reader to see his frustration.

LOWRY MOVES TO -1

After driving the green at 16, he two-putts for a birdie to move back to where he started the day on -1.

PARS APIECE FOR SPIETH AND GRACE

Spieth in particular is delighted with that one on 15 after an unlucky tee shot. Great up and down.

FIVE IN A ROW FOR OOSTHUIZEN

He birdies 16 as well to move to -3, two off the lead. Remarkable.

LOWRY PARS 17

It’s not quite the challenge we were hoping for but it has been a solid final round from Shane Lowry nonetheless. He’ll head down the 18th on -1.

HAS BRANDEN GRACE JUST GONE OUT OF BOUNDS?

What a time to fluff your tee-shot! Grace’s ball looks to have snuck underneath a mesh boundary fence. There’s no official word on whether it’s playable or not but he’s going to hit a provisional anyway.

If it’s OB, that’s game, set, match Spieth you’d feel.

LOUIS’S BIRDIE STREAK IS OVER

He can’t make it six in a row but a birdie at the last would see him take the clubhouse lead on -4 and turn up the heat on Spieth.

JORDAN SPIETH, TAKE A BOW!

That should be the winning of it. Jordan Spieth rolls in a 24-footer, full of break, for birdie and he moves to six-under.

It’s a double-bogey for Branden Grace who drops back to -3.

Spieth now leads by three shots and barring a spectacular collapse, it’s hard to see him losing it from here.

LOWRY BOGEYS 18, FINISHES ON LEVEL PAR

A costly final hole for Lowry but it has been another brilliant week. He’ll finish in a tie for 10th at worst.

HANG ON A SECOND!

Louis Oosthuizen has just birdied the last to take the clubhouse lead on -4. That’s a remarkable finish, coming home in just 29.

Why am I putting the brakes on the Jordan Spieth victory party. Well, he’s going to at least bogey the 17th and drop back to -5. That’ll make for a nervy tee shot on the last.

A DOUBLE BOGEY!!!

Spieth missed the putt back as well. He had the tournament won and now he’s only tied for the lead with Oosthuizen.

My word, I can’t believe this

So Jordan Spieth will tee off the par-five 18th needing a birdie to win the US Open. Par gives us a playoff. Anything worse and he’s outta here.

His record on the 18th this week? Par-Double Bogey-Par

His drive looks good though. Found the fairway.

DJ’S NOT DEAD YET

He has a strong birdie chance after his tee shot at 17. Make that and his destiny is very much in his own hands going down the last.

BIRDIE FOR DJ

He joins the gang on -4

Ah, that’s a superb approach shot from Jordan Spieth. I would say it’s a shot worthy of winning a Major but there’s no guarantee of that yet. It will leave him with about 15 foot for eagle — if he even makes a birdie, it will kill off Oosthuizen and leave Johnson needing a birdie of his own on the last.

Pretty unanimous reaction to Spieth’s second shot

Johnson has creased his drive down 18. Don’t go anywhere.

One second while I pick my jaw up off the floor

BIRDIE FOR SPIETH, INTO THE CLUBHOUSE ON -5

The eagle putt has the distance but it’s just to the left of the hole. He taps in for birdie and takes the clubhouse lead on -5.

Over to you, DJ.

Now seems like a very appropriate time to remind you that in the event of a tie, the US Open is decided by an 18-hole playoff.

Just sayin’.

Irrespective of what happens over the next five minutes, this has been one of the great final days.

MAGNIFICENT BY JOHNSON

By my guess, he’s left himself with a 10-footer for an eagle and to win the US Open. A birdie ties it.

If you’ve a horse left in this race, I feel sorry for your fingernails.

How about this? The last time a player birdied the 72nd hole to win the US Open was Bobby Jones back in 1926. Dustin Johnson has a chance to win it with an eagle.

Day holes out for four-over par 74. Over to you, Dustin…

12’4″ is the official measurement

NO

It just didn’t break as much as he thought it would. And there’s a little bit of work in the putt back…

MISSED IT

JORDAN SPIETH IS YOUR 2015 US OPEN CHAMPION

Apologies if there’s a bit of a gap between updates here. Genuinely struggling to comprehend what had just happened.

Johnson had a three-footer back to force the playoff and missed it. Missed it by a bit.

So Jordan Spieth becomes the first player to win the Masters and the US Open since Tiger 13 years ago.

He now holds two of the Majors; the other two belong to Rory McIlroy.

St Andrew’s can’t come quickly enough.

That’s it from us for tonight — it’s 3.30am after all — but you can be sure that there will be plenty of reaction to that drama tomorrow.

Thanks for reading.