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Dorothy Wall
Ireland forward on BBC Two

It's been an incredibly disappointing period for me [with my injury] but my goalposts have changed in terms of what matters and it's about a huge win.

You'd expect New Zealand and Ireland to go through in the pool. You don't know what could happen but I'm backing Ireland today.

For the Japan game, I'm expecting it to be fast-paced and physical. Japan head coach Lesley McKenzie has placed an emphasis on the conditioning of the players in the lead-up to the World Cup.

Japan are notorious for being a quick team, but they have been working hard on the physical side and I'm sure they will have something up their sleeve when it comes to set-piece time.

They have a strong front row, too, especially if Sachiko Kato is starting. I played with her in Exeter: she's a strong scrummager and is lethal around the tryline from two or three metres out.

For Ireland, it's about playing smart rugby and outworking Japan but I have seen enough from our girls in the warm-up games to be confident about an opening victory in Northampton on our return to the biggest stage for the first time in eight years.

Orla Bannon
BBC Sport NI at Franklin's Gardens

It's already hot and humid inside Franklin's Gardens yet both the Ireland and Japan squads have been out for some time doing their respective warm-ups.

The Irish girls said after watching the opening game of the tournament on Friday night they had fire in their bellies and could not wait to get their campaign started, so no wonder they've been out on the pitch for so long already.

It's time for the talking to stop and the action to start, but it's taking a little time for the stadium to fill up - partly because of the lovely atmosphere outside.

There's live music, lots of food and drink stalls and the Ireland and Japan fans are lapping it all up before the serious business starts.

Image source, Inpho

Co-captain Edel McMahon is confident that Ireland's lack of World Cup experience will not "shake" the squad as they prepare to face Japan in their opening game.

Having failed to qualify in 2021, hooker Cliodhna Moloney-MacDonald is the only player with World Cup experience in the Ireland squad, with five appearances in the 2017 tournament.

But McMahon, who is set to win her 35th cap today, says the squad have been using the experience of Sevens players such as Stacey Flood and Amee-Leigh Costigan, who represented Ireland at last year's Paris Olympics.

"To be honest, we did speak about that when we first came in for pre-season," said back row McMahon, who has recovered from injury to start against Japan.

"But we also have girls who have been at the Olympics, being at the biggest world stage you can imagine into sport, so tapping into those headspaces like Leigh, Stacey and all the girls, they all have different experiences of what it's like to play on the world stage.

"We definitely spoke about it as a group but you just don't feel like it shakes this group. It doesn't feel like it's the first World Cup for these girls, they just take it in their stride. It's cool to see that headspace and mentality that they have."

Image source, Inpho

Ireland co-captain Edel McMahon says the squad are behind Shannon Ikahihifo after the forward revealed she has been diagnosed with breast cancer.

New Zealand-born Ikahihifo, who has won three Ireland caps, was part of the training squad for the Women's Rugby World Cup but was not selected in the final panel for the tournament.

In a post on Instagram on Friday, the 30-year-old Trailfinders player said: "Crazy to think that one day you can be running around on the rugby pitch feeling completely fine, then five days later you're sitting in a hospital room being told you have cancer.

"Still a little in shock if I'm honest, but I'm so blessed to have the most amazing husband, family, and friends that always carry when things start to feel a bit heavy.

"Fair to say she's been a pretty tough few weeks. But lucky we're tougher."

Here is how Ireland's Pool C fixtures look. They'll be back in Northampton next week to take on Spain before finishing with a huge clash with world champions New Zealand in Brighton in a fortnight's time.

Image source, Inpho

Image source, Inpho

Ireland back row Brittany Hogan said she has used rugby as a way to cope with the grief of losing her father suddenly in 2023.

Ahead of her first appearance at the Women's Rugby World Cup, Hogan has opened up about the impact of her father's and grandfather's deaths and how the support of her team-mates helped her get through a difficult time.

"I lost my dad two years ago and then my grandad in August. They were two father figures in my life that are gone, and I am playing for them," the 26-year-old told BBC Sport NI's Orla Bannon.

"My dad got stung by a wasp on the way home from work and went into anaphylactic shock. He had to pull over in the car and my little sister was calling people to help, so without her or the help of the air ambulance, we wouldn't have been able to say goodbye.

"It was traumatic and tragic, it was a hard period of time, but we've had a few more sudden deaths in the group, and we've grown to know how to deal with it and we rallied around each other."

During the last World Cup, Ireland watched with envy from home after failing to qualify for the first time since 1991. Three years on, it's a different story. Not only are Ireland in the tournament, but I think they should be targeting a semi-final.

This would have been inconceivable a few years ago. I was on the pitch when we lost to Scotland in the World Cup qualifiers in Parma in 2021.

It was a dark time for us, both on and off the pitch. As a squad, we were working full-time and pretty much training and playing full-time on top of that. We'd work Monday to Friday, go into camp on Friday evening, do close to eight sessions and come back out on Sunday night before going back to work on Monday.

It was a stressful existence and we didn't even have a World Cup to look forward to at the end of it.

Thankfully, things have since moved in the right direction since. With more investment and contracts for players, Ireland have reaped the rewards. There have been back-to-back third-place finishes in the Six Nations and a promotion to WXV1, where we earned a memorable win over New Zealand last year.

That win over the Black Ferns means Scott Bemand's side must target first place in Pool C. If they do that, it would likely mean facing Italy or South Africa in the quarter-final and Ireland are capable of beating either.

That is all to come. For now, Ireland are focused on facing Japan and, despite some high-profile injuries, the squad is in good shape before Sunday.

Image source, Inpho

The build-up to Beibhinn Parsons' first Women's Rugby World Cup has been, to put it mildly, less than ideal.

This time last year, the 23-year-old wing broke her leg while representing Ireland Sevens in the Paris Olympics.

As a result, Parsons missed Ireland XV's memorable WXV1 campaign, which included an enthralling 29-27 win over world champions New Zealand.

A week on from making her comeback, Parsons suffered a second leg break while playing in the World SVNS Series leg in Cape Town in December, ruling her out of the 2025 Women's Six Nations and putting her World Cup hopes in doubt.

But the speedy Connacht back recovered in time to make Scott Bemand's squad and will make her World Cup debut against Japan.

"It's been a tough year, but I'm one of the lucky ones where the timing worked out," Parsons told BBC Sport NI.

"I'm thinking of all the girls that are injured now. It's difficult for them to miss out on a World Cup. It's funny, you think things aren't going your way but I've been lucky enough to have enough time to recover and make the squad."

Image source, Inpho

Ireland co-captain Sam Monaghan says it will be "a surreal moment" when the long wait for the side to play at a Rugby World Cup finally ends.

Stepping out against Japan for an opening Pool C fixture at Franklin's Gardens in front of a sellout crowd will be the culmination of three years preparation for just such an occasion.

Since failing to qualify for the last World Cup in 2022, and then finishing bottom of the Six Nations without a win the following year, Ireland have worked relentlessly to turn things around and want to show the world they are now a force to be reckoned with by going deep into this tournament.

"It will be such a special moment for the whole squad, but once we cross the whitewash it's going to be all about that 80 minutes and trying to go as hard as we can," said Monaghan.

"We have been building towards this for the last three years really, but there is no pressure, we're going to do what we do, focus on us and enjoy it as much as we can."

Co-captain Edel McMahon has recovered from injury to start in Ireland's Women's Rugby World Cup Pool C opener against Japan in Northampton.

Exeter's McMahon did not play in either of Ireland's two warm-up games because of a knee issue, but is named at open-side flanker in one of four changes from the warm-up defeat by Canada on 9 August.

McMahon will lead the team alongside Sam Monaghan, who starts in the second row. Monaghan's inclusion at lock means Fiona Tuite moves into the back row alongside Ulster team-mate Brittany Hogan and McMahon.

"I was disappointed to miss out on the warm-up matches," said McMahon.

"I was there or thereabouts but we made the best decision to make sure I was in the best condition for this weekend. I'm really excited and just buzzing to get going."

Ireland: Flood; Parsons, Dalton, Higgins, Costigan; O'Brien, Reilly; O'Dowd, Jones, Djougang, Campbell, Monaghan (co-capt), Tuite, McMahon (co-capt), Hogan.

Replacements: Moloney-MacDonald, Perry, McGrath, Corri-Fallon, Moore, Lane, Breen, McGann.

Japan: Nishimura; Matsumura, Furuta, Hirotsu, Imakugi; Otsuka, Tsukui; Kato, Kuge, Kitano, Sato, Yoshimura, Kawamura, I Nagata (capt), Saito.

Replacements: Taniguchi, Mine, N Nagata, Sakurai, Hosokawa, Abe, Yamamoto, Hatada.

Right, with kick-off fast approaching, let's have a look at the line-ups...

Ireland will be well supported in Northampton today - their fans haven't had to travel too far in fairness!

Image source, Inpho

Image source, Inpho

Image source, Inpho

Ireland have waited eight years for a return to the biggest stage.

It has been a tough journey. From failing to qualify four years ago to a subsequent breakdown in the team's relationship with the union's, Ireland have had to overcome major obstacles before getting another crack at the World Cup.

They have, however, been on an upward curve over the past year. Last year's WXV1 adventure yielded a stunning win over world champions New Zealand before a second straight third-place finish in the Women's Six Nations.

Now, with all the build-up out of the way, today is about launching their tournament on a positive note.

Scott Bemand's side started slowly in their two warm-up fixtures against Scotland and Canada, so there will surely be an emphasis on setting down an early marker.

Thanks for joining us. You can watch or listen to the game from 11:45 BST on this page.