Boos for Jens Larsen as he charges away down the left but a well-timed boot halts his run and prompts cheers from the home crowd.

Denmark straight on the front foot. They want an early goal to force the hosts into having swift a rethink about their tactical approach.

One last, huge roar from the home fans and we're under way!

Image source, Reuters

I'm a bit surprised that Daryl Murphy got the nod tonight instead of Shane Long. The latter would have been ideal for putting pressure on the Denmark defence and giving them something to think about. That said, he hasn't scored in 28 competitive games...

We've just had the national anthems. Hairs standing up on the back of my neck after the entire stadium belted out the Irish one. Stirring.

Image source, Reuters

Republic of Ireland manager Martin O'Neill tells Sky Sport: "The players are ready, we may have to make changes as the match goes on, but we have gone in solidly then see what develops.

"I was asked, 'are you preparing for 120 minutes, penalties?' It only takes a second to score a goal and that changes everything. The players have to win the game, this is it. Whether that takes a long time or not, I do not know.

"The crowd will play a big part tonight. Let’s make it count."

Image source, Reuters

Image source, Getty Images

Denmark have not lost a single international fixture in 2017, winning four and drawing four of their eight games and conceding just four goals.

They haven't suffered defeat since October last year, when they lost 1-0 to Montenegro.

Here we go, Republic of Ireland fans. The time has finally arrived.

The players walk out of the tunnel and onto the Aviva Stadium pitch. Huge noise greets them. Fantastic atmosphere. Will the supporters prove to be the 12th man?

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BBC pundit and former Republic of Ireland midfielder Kevin Kilbane, one of those in that team that beat Iran 16 years ago, is confident there is more to come from Martin O'Neill's side.

Watch the video below to see what Kilbane had to say.

The last time the Republic of Ireland reached a World Cup they also did it by coming through a play-off.

The Republic, then managed by Mick McCarthy, beat Iran 2-1 on aggregate back in 2001 to reach the 2002 World Cup.

Denmark have appeared at four World Cup finals but this is their first appearance in a play-off.

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Denmark boss Age Hareide is not even contemplating the possibility of losing to the Republic of Ireland.

In fact, so confident is he in his side being able to get the job done inside 90 minutes that Denmark have not practiced penalties.

"We won’t need them,” said Hareide.

"We only have to score one goal to get to a World Cup, that is a fantastic opportunity which we have to take."

Away goals count double in this game meaning if it ends 1-1 after 90 minutes then Denmark will progress.

Nik Levis: When Ireland parks-the-bus, it's "Brave", "Tough" and "Gritty". When Sweden does it, it's "Boring", "Unimaginative" and "Dour".

Richard: I'm in Cardiff for the Wales game wondering what might have been. But I'm fully behind the Republic of Ireland. No hard feelings, lads. Go and get to the World Cup!

Get in touch via #bbcfootball, text in on 81111 (UK only) or post a comment on the BBC Sport Facebook page.

We've got a veritable smorgasbord of international action for you to get your teeth into tonight.

Fancy following England's friendly against Brazil? Live text and 5 live commentary is here.

Want to watch Wales take on Panama in a friendly? You can do that here.

Image source, Getty Images

Some dedication to the art of fancy dress here. Top effort.

These two make regular appearances at Republic of Ireland games dressed like this, with the young lad's dad apparently going through passport control, external dressed as The Hulk on his way to last year's Euros.

Unless they are happy to go down the play-off lottery route, the Republic of Ireland will have to be a bit more adventurous in this game and that will be good news for this man...

Image source, Getty Images

Christian Eriksen struggled to make an impact in the first leg and that was largely down to the lack of space he was afforded.

If the hosts open up a bit more, he could well find more room to produce a moment or two of magic.

Eriksen has created 38 chances in World Cup qualifying, more than any other player. He'll be at the centre of everything Denmark do tonight.

Image source, Getty Images

The lack of goals in the World Cup play-offs doesn't bode well for this game being done and dusted inside 90 minutes. Even more so when you consider the Republic of Ireland's first-leg display.

They put on a defensive masterclass to frustrate Denmark, prompting Danish midfielder Thomas Delaney to liken the Republic of Ireland to a tin of beans.

"We tried and tried," he said. "It was a bit like opening a can of baked beans with your bare hands - it takes time."

Is it even possible to open a can of beans with your bare hands? Assuming it doesn't have a ring pull.

Paul McGrath summing up how pretty much every Republic of Ireland fan is feeling right now.

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So just how nervous are you about tonight, Republic of Ireland fans? What was your tactic to get through the day and are you feeling confident that your side can get the job done tonight?

Let us know via #bbcfootball, text in on 81111 (UK only) or post a comment on the BBC Sport Facebook page.

The teams are in and Martin O'Neill makes one change to the Republic of Ireland team from the first leg as captain David Meyler returns to the side. He replaces Callum O'Dowda, who drops to the bench. Daryl Murphy retains his place in attack.

Two changes for Denmark as Chelsea defender Andreas Christensen starts, as does RB Leipzig forward Yussuf Poulsen. Leicester keeper Kasper Schmeichel is once again in goal while Tottenham's Christian Eriksen is also in the first XI.

Image source, .

Image source, Getty Images

Think of the play-offs and you may often think of twists, turns and last-second drama.

Troy Deeney's dramatic last-minute strike against Leicester 20 seconds after the Foxes had a penalty saved comes immediately to mind. Or - going back a fair bit - Manchester City coming back from two goals down to eventually beat Gillingham on penalties.

But play-offs these days just seem a bit, well, dull. Take the last lot of World Cup play-offs:

13 November - Italy 0-0 Sweden

12 November - Greece 0-0 Croatia

12 November - Switzerland 0-0 Northern Ireland

11 November - Denmark 0-0 Republic of Ireland

11 November - New Zealand 0-0 Peru

10 November - Honduras 0-0 Australia

10 November - Sweden 1-0 Italy

Six of the last seven games have ended goalless.

Too much at stake?

Image source, Getty Images

For Republic of Ireland fans, tonight is the biggest night for some years.

Their side hosts Denmark in the second leg of their World Cup play-off tonight knowing victory will secure their place on the plane to Russia next year.

Ireland have not appeared at a finals since 2002 and, if my colleague is in anyway representative of the vast majority of Irish supporters, then it's been an agonisingly nervous wait for tonight's game.

Massive.