Early blow for Ireland. Paul Stirling, a reliable purveyor of tonk, is back in the hutch. He tries to whip a straight one from Adil off his legs and plays all around it. You can see him grimace beneath his helmet on the replay as he realises the ball is about to thud into his pads. Don't bother reviewing that.

Scorecard

Image source, ALLSPORT

BBC Radio 5 live sports extra

Image source, BBCTMS/TWITTER

Ever wondered what the view from the commentary box is like at the Adelaide Oval? Wonder no more. Here's the TMS duo of Jonathan Agnew and Michael Vaughan looking out on the action.

Tune into their TMS chat by clicking the 'Live Coverage' tab on this page.

Sohail continues. Stirling is away with a stout push into the covers - 40-year-old Misbah gives chase and keeps it to two. Sohail is cramping the batsman well with a tight line, but Stirling manages to pick up another single into the off-side. Steady start for Ireland.

Michael Blighe: I really hope Ireland make it, for the sake of association cricket (and also for St Patrick's Day). Would be beyond epic.

Ilyas Najib: There's plenty of nervous energy, I feel very uneasy at the thought of Pakistan chasing in this game.

Ehsan Adil, playing his first game of this tournament, opens up from the other end. He'll be feeling the nerves - can Ireland target him early doors? Oh yes! Porterfield picks up the length early and slugs him over midwicket for a one-bounce four. Crunch! Adil can't afford to bowl too short at his modest medium pace. He errs again and Porterfield picks up two more with a slightly mistimed pull.

Dear oh dear, the Windies don't do things the easy way. Their cruise towards the 176 target has entered slightly choppy waters with the loss of a second wicket in quick succession. Andre Russell's dismissal for seven is similar to that of Charles as he gets right underneath a drive and Amjad Javed steadies himself to claim the return catch.

Michael Vaughan
Ex-England captain on BBC Test Match Special

"Will Porterfield has done the right thing by choosing to bat first. Ireland have decided to get a score on the board and it is down to this pair to send a message to the dressing room. They have to make a flying start."

Stephan Shemilt
BBC Sport in Adelaide

"When the Beatles sang about a sea of green, I don't think they had a cricket match in mind. That's what we have in Adelaide, with supporters of both teams almost all in their various greens. Outside, there's a stage playing host to some Irish dancing. Where do you find Irish dancers in Adelaide?"

Good start by Sohail Khan, full and just a hint of swing. The first ball is stoutly defended by Will Porterfield; the second is an absolute jaffa, pitching just outside off and just shaping back to beat the tentative prod of Porterfield.

Porterfield is usually the more circumspect of this opening pair - he's the man who will try to bat 50 overs and play the anchor role for Ireland. He's away with a clip of his hips for one.

Will Porterfield and Paul Stirling stride out to the middle. Sohail Khan, wearing just a dab of zinc cream on his nose, has the new nut for Pakistan. We're ready to go!

Image source, ALLSPORT

Anthem time in Adelaide. A lusty rendition of 'Ireland's Call' from the Ireland boys - they look pumped for this. Pakistan, clad in a not entirely dissimilar shade of green, look focused. But the nerves must be jangling inside - how will they go without their strike bowler?

Back to Napier for a moment where the West Indies have just lost their third wicket. Johnson Charles has proved a more than adequate stand-in for Chris Gayle, but he's out for 55, mistiming a drive and skying a catch to mid-on.

Let's sketch in that picture a little more fully for you.

If Ireland and Pakistan finishes in a tie or a no-result, both teams qualify, and the West Indies go home. Nice and simple.

If Ireland lose, they are almost certainly out - only a miracle result for the UAE against West Indies could save them. Pakistan would qualify in third place, along with the West Indies in fourth.

If Ireland win, they are definitely through in third place. Here's where it gets a little tricksy though. Pakistan could still qualify with a defeat - but they'd need the Windies to make a bit of a hash of their run chase. If the Windies get over the line within 36.2 overs, they are definitely through - meaning Ireland v Pakistan would be a winner-takes-all contest.

Image source, ALLSPORT

Plenty. Qualification or elimination; ignominy or glory; triumph or disaster. It's all on the line here.

If Ireland win today, they are definitely through to the knockout stages of the Cricket World Cup for the first time in their history. Not only would it be a huge moment in the history of Irish cricket, it's no exaggeration to say that what happens here could have repercussions for the future of Associate cricket - amid a backdrop of plans by the ICC to reduce the number of teams at the next World Cup.

And what of Pakistan? Lose today and they are almost certainly - more on that later - out. Elimination at this early stage would be a disaster for such a proud, cricket-mad nation, and it would be the second time in the last three World Cups that they'd failed to make the last eight. Failure is quite simply not an option for Misbah-ul-Haq's side.

Big news from the toss. Pakistan quick bowler Mohammed Irfan - arguably their bowler of their tournament so far - is out injured, so Ehsan Adil takes his place. No Younis Khan at 3 - Sohail Khan comes in at first drop. Ireland are unchanged.

Ireland XI: Will Porterfield (capt), Paul Stirling, Ed Joyce, Niall O'Brien, Andrew Balbirnie, Gary Wilson (wk), Kevin O'Brien, John Mooney, Stuart Thompson, Alex Cusack, George Dockrell.

Pakistan XI: Sarfraz Ahmed (wk), Ahmed Shehzad, Haris Sohail, Misbah-ul-Haq (capt), Sohaib Maqsood, Umar Akmal, Shahid Afridi, Wahab Riaz, Sohail Khan, Rahat Ali, Ehsan Adil.

Morning all! If you've just joined us, welcome. If you've been with us from the start, full marks for your commitment.

It looks like the West Indies are cantering to victory against UAE - time to turn our attention to the main course in this nocturnal cricketing banquet: Ireland v Pakistan.

It's the biggest day in the history of Irish cricket, and it's not exactly any old match for Pakistan either. This one could be an absolute belter.

Thanks JJ. So, the lights are coming up, the booze has run dry, and the DJ is playing 'Closing Time' by Semisonic. The interminable disco of the World Cup group stage is almost at an end, and it's time for Ireland and Pakistan to have one last dance.

But before the night is over, there's still plenty left for these sides to do. They've spent the evening flirting with qualification, without ever quite managing to seal the deal. Now it's time for one of these teams to make their move.

One last dance. Will it be an Irish jig, or will Pakistan rediscover their tiger feet?

Image source, ALLSPORT

Fifteen minutes until the big match of the day begins in Adelaide. Ireland. Pakistan. Winner takes all (probably). Here's our colleague James Gheerbrant to talk you through all the action.

And, of course, we will be keeping you up to date with the West Indies chase.

Johnson Charles waves his bat in the direction of the West Indies balcony - that's because he has just notched his third ODI half-century. Decent innings from Charles, the injured Chris Gayle's replacement, as the West Indies edge towards the win that they need to reach the last eight. Moments after reaching his half century, he slams the ball through third man for another boundary as the West Indies pass the 100 mark.

News from Adelaide. Ireland have won the toss and decided to bat first against Pakistan.