They've been a rock-solid couple closing in on four years but that won't stop Australian Jillaroos teammates Karina Brown and Vanessa Foliaki from putting their relationship aside in the inaugural women's State of Origin clash at North Sydney Oval on June 22.

Brown captained the Queensland women's side last year while Foliaki, who hails from NSW country town Orange, will start at lock for the Blues on Friday night.

The pair became an item in 2014 after they were selected for the Jillaroos and have dealt with competing against each other on several occasions.

But they admit next week's Holden State of Origin clash shapes as their biggest relationship challenge yet after the pair detailed how passion for their respective states matches the love and compassion they have for each other.

They have been open about their relationship in the women's rugby league ranks and has never been an issue among their teammates and support staff.

In a rare glimpse into their unique situation, the pair sat down with NRL.com to publically discuss their relationship for the first time and the challenges that come with competing against each other.

Brown admits she's the softer person in the relationship but describes Foliaki as ruthless around State of Origin week.

Loving couple off-field; fierce rivals on-field

"She would block my number, that's how serious it would get," Brown told NRL.com.

"She never got [a message I sent her one year] and it was a nice one saying I hope you don't get injured and that it's just a really competitive game.

"I'm hoping this year I get maybe a little bit of love ... [maybe] one message."

A bemused Foliaki confirmed she takes a ruthless approach during Origin week, but the pair agreed it had shaped their relationship today.

In the couple's loungeroom at their home in Brisbane is a framed Blues jersey on the wall owned by Foliaki – a friendly reminder for Queensland skipper Brown to see each day after NSW managed to end a 17-year reign of Maroons dominance in 2016.

"Everyone that I've played with for NSW knows when I'm in camp, it's just Origin – I'm not with Karina," Foliaki said.

"I'm a Blues player and that's straight down the line. I'm really focused on the job, it's a big occasion.

"Karina is messaging me, and I'm like 'she's a Queenslander', and I put my phone away. She's a Queenslander and I want to beat her."

Brown said it was her partner's passionate nature that enabled her to not take it personally as they each put on a professional front when it comes to rugby league. They faced off against each other - Brown for Queensland City and Foliaki for NSW Country - at the Harvey Norman National Championship on the Gold Coast earlier this month.

But their banter outside of the game is something to behold – even as they both try to reflect on who initiated their relationship.

Everyone that I've played with for NSW knows when I'm in camp, it's just Origin – I'm not with Karina. Vanessa Foliaki

"We went out to have a few commiseration drinks [after a loss to the Kiwi Ferns]," Brown said.

"I saw her eyes light up and she came over, bought me a drink and the rest is history."

Foliaki immediately baulked at Brown's description.

"Complete opposite," Foliaki laughed.

"Karina saw me across the room. We were drinking at the bar and she decided to shout everyone a drink, have a skolling competition and couldn't beat me. I smashed her. It started from there."

The pair insist the women's rugby league family has been supportive of their relationship, particularly in camps, along with both sides of the couple's families.

"Everyone wants us to get married," Foliaki said.

"Being a part of the Jillaroos and how open everyone was to our relationship helped a lot.

"I think it's more accepted now and the Jillaroos make it feel like home. The coaching staff are supportive. We're feeling all the love."

The prospect of marriage and children has been discussed, just don't ask either who is the one to propose or carry a baby for nine months.

With women's rugby league ramping up in 2018 there is no better time to be involved in the game and the pair have already set new goals with the upcoming Holden Women's NRL premiership.

Both are expected to join the Sydney Roosters in September.

"We've had this discussion a few times," Brown said about the prospect of getting married and starting a family.

"We've got to buy a house first ... and Ness wants a goat."

That's if, of course, they can both get through Origin week.

Holden Women's State of Origin is ready to kick off a new era in elite women's sport. Witness the spirit of Origin manifest on the iconic North Sydney Oval on Friday, June 22. Tickets available now!