Star player Sam Kerr ruled out of Australia's opening two Women's World Cup matches with injury

Sam Kerr of Australia is seen prior to the FIFA Women's World Cup Australia & New Zealand 2023 Group B match between Australia and Ireland at Stadium Australia on July 20, 2023 in Sydney / Gadigal , Australia. (Photo by Maddie Meyer - FIFA/FIFA v

Sam Kerr will miss Australia's opening two games of the Women's World Cup because of an injury that wasn't revealed publicly until the starting lineup was announced about an hour before kick off Thursday against Ireland.

Kerr has been the face of a heavy marketing campaign ahead of the tournament being co-hosted by Australia and New Zealand. She is Australia's captain and leading scorer and her absence is a massive setback for the Matildas.

The star striker sustained a calf muscle injury during practice on Wednesday but it wasn't confirmed until Stadium Australia was almost full with expectant fans. She'll also miss Australia's second match against Nigeria in Brisbane next week.

"I wanted to share this with everyone so there is no distraction from us doing what we came here to achieve," Kerr wrote in an Instagram post distributed by the team. "Of course I would have loved to have been out there tonight but I can’t wait to be a part of this amazing journey which starts now."

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The team said Kerr's condition would be assessed before the Matildas face Olympic Canada in their last game in Group B. With 63 goals in 120 international games, Kerr had been one of the favorites to win the Golden Boot at this World Cup.

The Chelsea forward is considered one of the finest goal-scorers in the world and is an iconic figure in Australia.

Kerr headed into the competition having helped Chelsea win the Women's Super League in England and the FA Cup.

She had spoken on Wednesday of performing her traditional back flip celebrations if she scored against Ireland.

But any such moments will have to wait at least until Australia's last group game against Canada in Melbourne on July 31.

Mary Fowler, who has Irish heritage, replaced Kerr in Australia's attack. Fowler, one of five Australian players on World Cup debut against Ireland, scored the winner in the Matildas' win over France in a warmup match last week.