Vera Pauw's (60) team, ranked 22nd, know they are in tough against 10th-ranked Australia in Thursday's tournament opener in front of what is expected to be a record crowd of 82,500 - and a sea of green and gold - at Stadium Australia.
Sky Ireland's campaign for Ireland is "Outbelieve," and Pauw said it is a motto The Girls in Green have taken to heart.
"That word will end up in the dictionary because we outbelieve we can do something special here," said the Dutch coach. "That is how we ended up here because we outbelieved. We did something that nobody expected."
Ireland clinched their World Cup berth with a nerve-jangling victory over Scotland in a play-off at Hampden Park. Amber Barrett (27) scored the lone goal, and then kneeled, tugging at her black armband, in tribute to the 10 people who died in a gas explosion days earlier in her home county of Donegal.
Ireland and Colombia abandoned a friendly on Thursday in Brisbane after just 23 minutes, after it was deemed overly physical. Midfielder Denise O'Sullivan (29) was taken to hospital for a leg injury, but Pauw said she is healthy and will play Thursday.
Captain Katie McCabe (27) said Ireland do not fear the physicality of any team.
"We're Irish, we don't shy away from physicality. It's ingrained in us in the hardworking team we are," she said.
On the eve of their debut, the Arsenal player declined to share what motivational message she would give her team mates before they walk onto the pitch, but keeping their love of the game front of mind will be part of it.
"I started playing football for the love of it and the enjoyment we bring playing with each other," McCabe said at a news conference Wednesday. "Myself and the girls have been on a journey...it's something we've all worked really hard towards.
"We'll just be embracing every moment, taking it in, having that moment to ourselves and then when the whistle blows be ready."
McCabe detailed her squad's hardscrabble journey in her piece for The Players' Tribune entitled The Story of an Irish Underdog.
"To really get us, you have to know about the days when we had no money, no respect, no nothing," she wrote. "When we didn't get paid. When we were training on pitches that looked like potato fields. When we had to borrow tracksuits, and then get changed in airport toilets to hand them back."
People in Ireland often reference the men's World Cup debut in Italy in 1990, McCabe said. She hopes people back home will recall the women's debut in similar fashion, that it will be their "Italia '90."
"'The Irish girls in Australia and New Zealand 2023. Ahhh, remember that summer?' That what we're fighting for," she wrote. "Back home in Ireland, I know that lots of little girls will be watching us...I'm just hoping, with all my heart, that some of them will be sitting there thinking, 'One day, I'm going to do that.'
"If that happens, we have already won."
Ireland, who were greeted by a throng of green-clad fans at Sydney Airport when they landed on Thursday, play Olympic champions Canada on July 26th and Nigeria on July 31st.
"We do know the pressure that we will be on," Pauw said. "It's the first time that we at this world stage which is massive, the way we've come here is something to be really, really proud of. We are very realistic in our chances here. But we play every game to win."
