The Women's World Cup on Thursday, roared to life with high drama and unexpected setbacks as Australia, rocked by the late withdrawal of star striker Sam Kerr due to injury, overcame Ireland's fierce resistance to secure a hard-fought 1-0 victory in their opening match.

The atmosphere inside Stadium Australia was electric as Steph Catley's 52nd-minute penalty ignited an eruption of joy among the 75,784-strong crowd.

Yet, there was an air of trepidation and concern after news of Kerr's injury emerged just an hour before kick-off, leaving the home team without their iconic captain for the clash against Ireland and the upcoming game against Nigeria.

By the final whistle, Kerr, arm-in-arm with her teammates, celebrated the team's victory, displaying a united front even in her absence on the field.

Her injury casts uncertainty over her return for the critical encounter against Canada in the team's last Group B match.

Mary Fowler, with Irish heritage, stepped up to replace Kerr in the attack, but the void left by the country's all-time leading scorer was evident.

Kerr's absence impacted Australia's offensive prowess, leaving them struggling for ideas and cutting edge against a resilient Irish side.

Amid roars of encouragement from home fans, Australia faced a challenge in breaking the deadlock in the first half.

However, fortune favored the Matildas as Marissa Sheva's challenge on Hayley Raso in the box awarded them a penalty.

Catley displayed composure, sending Ireland's goalkeeper Courtney Brosnan the wrong way with her left foot, converting the decisive spot-kick.

While Ireland, participating in their first World Cup, showcased determination and resilience, their late onslaught could not breach Australia's defense, thanks to goalkeeper Mackenzie Arnold's heroics.

The match's intensity reflected the opening day's emotion, with both co-hosts securing crucial victories as New Zealand edged Norway 1-0 in an emotional opener in Auckland.