Matildas left-back Steph Catley woke up with a feeling she would take a penalty against Ireland.

On Thursday night, the stand-in captain, deputising for the injured Sam Kerr with both the armband and penalty duties, delivered.

The Matildas were unsettled and nervous when Marissa Sheva bowled over Hayley Raso inside the penalty box at Stadium Australia.

In the 52nd minute, Catley stepped up, took a breath then buried it in the top corner, delivering Australia's first goal in their home Women's World Cup and what was ultimately the winner in a scrappy 1-0 victory.

"I knew I was on pens tonight and I am sort of second in line to take pens if Sam ever, for whatever reason, doesn't want to take it," Catley told reporters.

"But obviously with her out tonight I did know I was gonna take the pen. But I had a feeling I was gonna get one - I don't know why.

"When I woke up this morning I was like, 'I feel like I'm gonna take a pen today.'

"But when it happened, I just tried to relax. I like taking set pieces.

"So I just picked a spot, kept thinking about it, took a deep breath and then just hit it where I wanted to hit it and luckily it went in."

Catley, 29, was the only Australian to convert their spot-kick in the 2019 penalty shootout defeat to Norway in the round of 16.

Her first World Cup goal that counted clearly meant that bit more.

It was the same end of Stadium Australia where John Aloisi scored his spot-kick against Uruguay in 2005 that sent the Socceroos to their first World Cup since 1974.

The feat also came in front of a record Matildas crowd of 75,784 fans.

"We've had a lot of experience playing at home and we love playing in front of a home crowd, but we've never played to this type of occasion before," Catley said.

"The build up was incredible, as female footballers we've never felt or seen anything like it.

"So there was a lot of talk about just playing football, playing our game, relaxing into it and accepting that there was going to be sloppy moments, there was going to be nerves.

"So when that happened in the game, because we were expecting it, we were fine, we just recovered, kicked on and got the job done."