She is the defensive stalwart for the sporting team that has become Australia’s darling, yet after 18 years with the Matildas, Clare Polkinghorne has a clear-cut view of retirement: “I’ll definitely need a job.”

The 35-year-old will play her last game of professional football on Thursday in the Matildas’ friendly against Brazil, which is doubling as a fond farewell for the Queenslander. It will be her 168th international appearance, a record for an Australian footballer, and comes almost two decades after her debut.

“I was lucky to come in at a good time,” Polkinghorne said. “When I made my debut for the Matildas, we were starting to get, not full-time contracts, but contracts in place for players to be paid. It’s about recognising where we’ve come from, and there’s a lot of players that came before me that did a lot of hard work to get the conversations going, and throughout my career, the Matildas have really pushed in that space.”

The top Matildas are paid up to $200,000 per year by Football Australia under a pay deal struck last year, on top of their club salaries and separate work or endorsements. Sam Kerr reportedly earns upwards of $3m per year in total, but player pay drops quickly outside those like the Chelsea striker who occupy the highest echelon of women’s football.

As many as 16 of the 36 players initially selected by Matildas interim coach Tom Sermanni for the upcoming friendlies play in the A-League Women, where many young players receive the minimum wage of $25,750 for the 35-week season. Professional Footballers Australia has called for the league to embrace full-time professionalism within two years.

“Hopefully we can continue to grow that so that players can be full-time professional, both at club and international level, and not have to worry about that side of things, and they can put all their focus into football, being the best athletes they can be,” Polkinghorne said.

Sermanni’s squad has been whittled down by injury and absence to seven of the selected players, including star Mary Fowler who pulled out citing mental and physical fatigue. But the coach said he would field “our strongest team possible” for the first of four friendlies over the next two weeks, even if players have only just arrived from Europe.

“This is where I come from, old school: you want to turn up, you want to play,” Sermanni said. “You ask the players, do they want to play, I can guarantee 100% they want to be out there, and they want to be out there for 90 minutes.”

Polkinghorne is expected to start and be given a send-off in front of her home fans in recognition of her long career. “It’s really special for me to be able to come back to Brisbane and play one last game in a city that I grew up in, and a stadium that means so much to me, and in front of my family and friends and all the people that have helped me along my journey,” she said.

The three-time Olympian said she was lucky to play with the likes of former Matildas Dianne Alagich, Cheryl Salisbury, Kate McShea and Alicia Ferguson, who inspired her to be better, and that being part of the rise in women’s football has been a source of excitement.

“What I’m probably most proud of is seeing the growth of the game and being part of the team that has had such a positive impact on Australian football,” she said. “But I think the thing I’ll miss the most is definitely the relationships.”

Sermanni said he expected it to be a “very special night” and Polkinghorne deserved to go out on her own terms. “We use the word ‘legend’ very loosely these days, but I think it describes how she’s been not just a stalwart within the team on the field, but off the field,” he said.

Polkinghorne has also retired from club football, and plans to stay in Brisbane after the match for a break, before pursuing a career in coaching.

“Football has given me so much in my life,” she said. “It’s really important for me that I’m able to give back and continue to help the game grow and help the players grow, and hopefully pass on a little bit of my experience and knowledge to the next players coming forward.”