A quick reminder that you can listen to this match on both BBC Radio 5 live sports extra and BBC Radio Ulster by clicking the 'Live Coverage' tab at the top of the page.

The Millennium Stadium, as it always does on these occasions, sounds absolutely magnificent as the teams emerge.

Ireland, led out by captain Paul O'Connell, are in their familiar green, while Canada are kitted out in red.

Time for some anthems.

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So what do we know about Ireland's opponents Canada?

Canada's best result at the World Cup was reaching the quarter-finals in 1991, where they lost to New Zealand.

In 2011 they beat Tonga in their opening group match but drew with Japanand lost to France and New  Zealand.

Their record reads:

Played 25 Won 7 Lost 16 Draws 2.

So Ireland have never made it past the quarter-finals of a World Cup, but how will they get on this year? Now is your chance to have your say and vote on their chances.

Our vote is open now and will be until 15:10 BST. Results will be announced later on.

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Ireland have reached the quarter-finals six times in eight World Cups.

In 2011 they lost 22-10 to Wales in Wellington, New Zealand.

Their record reads: 

Played 30 Won 17 Lost 13

It isn't a big tournament without a message of support from a famous person. One Direction's Niall Horan has posted the following message of support to the Ireland team.

John Haughey
BBC Sport at the Millennium Stadium

"And so the World Cup is about to begin for Ireland.

"After losing their final two warm-up games against England, the Irish will be looking for a confidence-boosting win over the 18th-ranked Canadians.

"Despite their recent struggles, many pundits are tipping Ireland to reach the uncharted territory of a World Cup semi-final place.

"Joe Schmidt's side will look for a big win today to build confidence ahead of the tougher Group D tests against Italy and France."

Ireland coach  Joe Schmidt has just been talking to ITV Sport. He says: "This game has been a long time coming. It is inspirational seeing the level of support coming into the stadium but it will be about keeping calm before this game.

"We think our defence has been a little less than we normally expect. In the last two Six Nations we have conceded seven tries but we've conceded too many recently. Hopefully we will improve defensively.

"We have been focused on trying to get a positive start to the game. We saw last night that form goes out of the window and it's about just performing."

BBC Radio 5 Live Sports Extra

Image source, BBC Sport

Replacements: Benoit Piffero, Djustice Sears-Duru, Andrew Tiedemann, Jebb Sinclair, Richard Thorpe, Phil Mack, Liam Underwood, Conor Trainor.

Image source, BBC Sport

Replacements: Sean Cronin, Cian Healy, Nathan White, Donnacha Ryan, Chris Henry, Eoin Reddan, Ian Madigan, Simon Zebo.

Lock Jamie Cudmore will appear in a country record-equalling fourth World Cup when he leads out Canada this afternoon.

He skippers the side in the absence of Tyler Ardron.

And a contender for stat of the day - the average age of Canada's starting XV is 29 years and 164 days old, their oldest ever in a World cup match.

Image source, Getty Images

Ireland's Robbie Henshaw has been ruled out of this afternoon's match in the Welsh capital with a hamstring strain, so Luke Fitzgerald is named at inside centre.

Iain Henderson's recent impressive form has been rewarded by coach Joe Schmidt with a starting berth alongside captain Paul O'Connell in the second row.

And prop Cian Healy is set to make his return from injury off the bench as Jack McGrath starts in the front row.

As always we want your thoughts before, during and after the match. How do you see this one going? Which players are going to be vital? which battles are you looking forward to? How far do we reckon Ireland can go?  

Don't be shy, tell us your views and we will post the best messages on this page throughout the match. You can contact us on Twitter, using #bbcrugby or leave a message on the BBC Sport Facebook page.

So we've seen England begin their campaign with a 35-11 win over Fiji at Twickenham and underdogs Georgia have just gained their first World Cup win with a 17-10 success against Tonga.

But now it is our first Pool D action, a section that also includes France,Italy and Romania.

The top two will then go on to meet the top two from Pool C in the quarter-finals.

And, with New Zealand quite likely to win that particular group, the Irish would do well to avoid having to settle for the runner-up spot in their pool.

A month ago, of course, the answer would've been a resounding yes. But a wobbly 16-10 defeat at home by Wales on 29 August slowed momentum...

Image source, Getty Images

Before a disappointing 21-13 loss to England at Twickenham just seven days later brought it to a grinding halt.

Image source, Getty Images

So, what next for Joe Schmidt's men? Welcome to our coverage of Ireland's World Cup opener against Canada.

Back-to-back Six Nations titles, a coach boasting a mighty 78% win ratio heading into the summer warm-up games and all their key men, including talismanic captain Paul O'Connell, somewhere near full fitness.

Ireland have it all going for them, don't they?

Image source, Getty Images