Steph Catley has stood tall as captain in Sam Kerr’s injury-enforced absence to deliver the Matildas a 1-0 victory over Ireland in their Women’s World Cup opener.

Australia’s campaign suffered a hammer blow when Kerr was ruled out of Thursday’s night’s game and the subsequent game against Nigeria with a calf injury suffered in Wednesday’s final training session.

According to Football Australia, the Chelsea striker will be assessed after the Matildas’ second group B game against Nigeria in Brisbane on July 27.

Vice-captain Catley wore the armband and stepped up in the 52nd minute to take a penalty after Hayley Raso was brought down, coolly dispatching the winning spot kick into the top corner to send Stadium Australia into raptures.

The sellout crowd of 75,784 was a new Matildas record on home soil.

Kyra Cooney-Cross blocks the cross of Ireland’s Heather Payne. Photo: Getty

Mary Fowler replaced Kerr in Australia’s starting line-up against Ireland and was the only change to the team that beat France 1-0 in Melbourne in the final warm up.

Caitlin Foord led Australia’s attack in Kerr’s absence.

Coach Tony Gustavsson opted for Alanna Kennedy to pair with Clare Hunt in the centre of defence instead of veteran Clare Polkinghorne.

As expected, Ireland parked the bus, playing five at the back and giving the Australians a green wall of players to get through.

For more than 45 minutes, it worked.

The Matildas probed early without reward, struggling to break down the Irish and taking some nervous-looking loose touches.

Katrina Gorry was everywhere, controlling the game from midfield, while Raso’s frantic energy and pace kept the Irish on their toes and she had a fiery battle with Irish skipper Katie McCabe.

Australia’s best early chance arrived in the 27th minute when Raso nodded a Catley cross just wide, while Foord hit the side netting eight minutes later.

Australia broke through when Kyra Cooney-Cross lifted a diagonal ball into the penalty box and in the chaos, Marissa Sheva bundled over Raso.

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Foord initially picked up the ball but handed it off to Catley, who made no mistake in converting the penalty.

Fowler, Foord and Gorry had good chances to add to the lead but couldn’t put them away.

Australia looked nervous as Ireland pressed for an equaliser late but held its nerve.

McCabe sent in a dangerous corner in the 71st minute that Arnold punched to safety and three minutes later, Denise O’Sullivan sent a shot way over the bar.

-AAP