Karen Bardsley
Former England and Manchester City goalkeeper on BBC Radio 5 Live

The cameras were right in her face during the warm up and she looked incredibly disappointed.

You can imagine, the entire build up has been about you and then you can't play.

But she is a fighter and a champion and this is her stage. She will want to be back as soon as possible.

Emma Smith
BBC Sport reporter at Stadium Australia, Sydney

Sam Kerr back on the big screen on 23 minutes, in conversation with a team mate. Her face brought whoops and cheers from some of the home crowd.

It's hard to say that Australia would be better off had Kerr been fit tonight - they have barely created a clear chance so far, against this sturdy Irish back line.

Lovely turn and run by Mary Fowler from the centre-circle but the attack breaks down after she tries to bring in her team-mates supporting on the left wing.

No real chances yet for either side midway through the first half.

Emma Sanders
BBC Sport in Sydney, Australia

Image source, BBC Sport

Plenty of nerves at the fan park here in Sydney. Australia’s Ellie Carpenter is a popular player and gets a few cheers every time she gets on the ball. But it’s the Irish fans who are feeling a bit happier after the opening 23 minutes.

Karen Bardsley
Former England and Manchester City goalkeeper on BBC Radio 5 Live

Ireland are looking very confident.

Courtney Brosnan has a very high starting position, she's pushing Louise Quinn up the pitch. There's a very good connection across the back line, both in and out of possession.

Both sides are trying to work out when to go direct, when to hold possession, it's like the beginning of a chess match.

Heather Payne, who spent a large part of Ireland's qualifying campaign up front, is out on the right in this game and her pace gets her beyond her marker but her cross is cleared.

Emma Smith
BBC Sport reporter at Stadium Australia, Sydney

Ireland are the underdogs tonight and have been pushed on the back foot in these opening 20 minutes - however they are holding strong, and will be buoyed by a few stats.

Australia have lost their last three opening games at Women's World Cups. Four years ago, they were surprised 2-1 by Italy.

The Aussies have also never had a goalless draw in 26 Women's World Cup matches. Given the way Ireland have defended so far - plus just four goals conceded in nine qualifying matches - they could aim for a historic stalemate tonight.

Karen Bardsley
Former England and Manchester City goalkeeper on BBC Radio 5 Live

Some fantastic footwork there from Caitlin Foord.

Two against one, driving into the box. Dropped shoulder and a few quick touches.

Denied by some great defending though.

Caitlin Foord is starting to cause some bother with her movement and she forces the Republic of Ireland to concede another corner. Katrina Gorry is on this one but it is headed away.

Ireland are the able to break with Australia having committed numbers forward and for a moment Kyra Carusa appears to be in but Gorry gets back to save the day.

Image source, Getty Images

Australia win another corner, which Kyra Cooney-Cross sends to the back post but Clare Hunt can't direct her header on target.

A bit of panic just inside the Australia box as the Republic of Ireland free kick is knocked on by Kyra Carusa. There's a bit of head tennis before eventually the ball is scrambled away.

Australia have lost their last three opening matches at World Cups and that will give Ireland hope. They are having a decent spell of possession at the moment, with it ending as Katie McCabe is fouled.

Image source, Getty Images

Karen Bardsley
Former England and Manchester City goalkeeper on BBC Radio 5 Live

When I used to play against her she used to really wind me up, she always used to peck away at you.

Since retiring I've been able to watch her play more and really appreciate how good she is.

She's a physical player and has a great mentality. She just loves to win, she's so confident and so determined.

Now Ellie Carpenter tries to find the run of Caitlin Foord but overhits the pass and the opportunity is gone.

So far, Australia are coping well with the blow of losing Sam Kerr so close to their opening game.

Image source, Getty Images

Ellie Carpenter is away down the right and the Republic of Ireland look in trouble. There's not enough runners into the box, however, and Carpenter's cross is dealt with when it comes in.

Emma Smith
BBC Sport reporter at Stadium Australia, Sydney

Barely a minute into the game, and Sam Kerr's face already filled the big screen as the cameras flashed to her looking pensive on the Australia bench.

Her team mates have started this game well without her. An early goal would settle a lot of nerves.

Karen Bardsley
Former England and Manchester City goalkeeper on BBC Radio 5 Live

It is going to be key for Ireland to try and manage that Australia momentum.

They need to try to quieten down that home crowd down when they can. They're going to be getting an earful all night long.

Image source, Getty Images

A big roar from the home fans as Katrina Gorry times a tackle to perfection to stop Denise O'Sullivan from getting away down the left.

The Republic of Ireland are quite happy to sit back and try and catch Australia on the break.

Karen Bardsley
Former England and Manchester City goalkeeper on BBC Radio 5 Live

It's all Australia so far.

They have taken a really compact position to try and force the play down the Irish right hand side.

Good start for the hosts.

Cortnee Vine is finding a lot of space down the left for Australia and a good touch takes her into the area before the Republic of Ireland defence is able to clear.

Australia then win the game's first corner soon after but it is headed away.