Ooh, hello! Jonny Bairstow deals with the first ball - a full yorker - but he's struck on the pad with the second. Junaid likes it, there's a brief conflab, and Pakistan are reviewing it!

Image source, Reuters

There's no messing about from Jonny Bairstow. He's going to take the first ball of the innings. He's got Junaid Khan to contend with.

Image source, Reuters

England: Bairstow, Hales, Root, Morgan, Stokes, Buttler, Moeen, Rashid, Plunkett, Wood, Ball.

Pakistan: Azhar, Fakhar, Babar, Hafeez, Malik, Sarfraz, Imad, Rumman Shadab, Hasan, Junaid.

The national anthems are done - top marks to Alex Hales and Joe Root for enthusiastic singing - and the players are about to take to the field, once the fireworks have stopped going off.

Image source, Getty Images

Chris Woakes
England all-rounder on Test Match Special

I'm surprised Pakistan chose to field first. I don't have an explanation about why they'd do that. Maybe they don't think the pitch will deteriorate much? Eoin Morgan said he wanted to bat first so it is an interesting decision from Pakistan.

Pakistan, meanwhile, did what Pakistan often do: make life difficult for themselves.

Their seamers, led by Hasan Ali, brought about a Sri Lanka collapse as they lost four wickets for six runs on their way to being bowled out for 236.

Pakistan cruised the first 10 overs of the run chase before tripping from 110-3 to 162-7 in the blink of an eye.

However, taking advantage of some ropey Sri Lanka fielding, captain Sarfraz Ahmed made 61 as Pakistan chased the total down with 5.1 overs to spare.

Matt Smith: Disappointed for Roy, but hoping he works hard and comes back even better after being dropped.

Right, let's have a little recap of how these two sides found themselves in the semi-final.

England topped Group A and were unbeaten in their three matches, but it was their performance against Australia in the final match that was particularly impressive.

After being reduced to 35-3 - and that was a slight recovery from 6-2 - chasing 278, Ben Stokes and Eoin Morgan revitalised England after the rain break.

They took Australia's pace bowlers on, with Morgan dancing down the wicket to Josh Hazlewood's second ball and thrashing it to the boundary. Stokes scored 102 from 108 balls and Morgan made 87 from 81 as England secured a 40-run win on DLS.

Image source, PA

Now, you say that, Eoin, but the last time England played Pakistan - back in September 2016 - was here at Cardiff, and they lost the match by four wickets. However, England have won 12 of their last 14 ODIs against Pakistan.

England captain Eoin Morgan, speaking to BBC Sport yesterday: “Cardiff has always been a very good venue for us and the last game we had great support and a full house and everybody seems to get right behind us."

Stephan Shemilt
BBC Sport in Cardiff

Even spectators can cause a media scrum. The chap on the right is Mr Pakistan, from Birmingham. Only took him 30 minutes to get ready...

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So, let's talk about Jonny Bairstow. A harsh call to drop Jason Roy? Maybe. The right one? Yup.

Bairstow has scored three half-centuries in four one-day innings for England this year but has struggled to break into the England team on a permanent basis.

Here's what captain Eoin Morgan had to say about the Yorkshireman to BBC Sport...

I think this is the first time I've looked at a weather forecast and I haven't seen any raindrops. It's unheard of! Sunshine! All day!

England captain Eoin Morgan: "We would have batted first anyway. Throughout the competition, this pitch has shown to be better to set a target than chase one. Pakistan can beat any team in the competition on their day so we're preparing for their best."

Pakistan captain Sarfraz Ahmed: "England are a good team so we have to play positive cricket against them."

There's a change for both sides: Jason Roy will miss out for England, as expected. He's been replaced by Jonny Bairstow at the top of the order.

For Pakistan, Mohammad Amir had a back spasm before play and has failed a fitness test. He's replaced by Rumman Raees, while leggie Shadab Khan replaces Faheem Ashraf.

Ramiz Raja looks resplendent in a blue suit at the toss. It's Sarfraz Ahmed calls correctly and Pakistan will field first. Eoin Morgan says he "doesn't mind" having a bat first. It's lovely blue sky above in Cardiff.

Hello! I'm excited for this one because this could be a cracker. You still suspect England have a collapse in them, but a lot depends on Pakistan. They looked drab against India but their comeback against Sri Lanka the other day was professional and impressive. We're about to have the toss...

At stake today: a place in the Champions Trophy final, where either Bangladesh or India await.

And I honestly don't know which way this one's going to go. Will it be joy for England...

Image source, Reuters

Or can Pakistan spoil Eoin Morgan's party?

Image source, Reuters