When Katie Taylor steps into the ring on Saturday night to defend her titles and once again enthral Ireland, there will be a bittersweet tinge. After a singular career that pioneered women’s boxing, the super-lightweight champion and Olympic gold medallist is bowing out. She is 40 and it is to be her final bout.

“The end of an era, isn’t it?” said Trevor McMahon, her brother-in-law and founder of a gym where she trains. “It’ll be an amazing night but it’ll also be a little bit sad. Everything she did, it might not ever be achieved again.”

There is consolation in the manner of her farewell. Taylor will fight in front of an 80,000-strong roaring, pulsing crowd at Dublin’s Croke Park, the citadel of Irish sport, in a valedictory like no other.

Before tickets went on sale in June, some worried that a boxing match might not fill such a vast stadium. The event out in 17 minutes.

Westlife and other musical acts have joined the bill, adding to the sense of extravaganza. The national broadcaster, RTÉ, will broadcast proceedings free to air, so every home and pub can tune in for Price’s showdown with Flora Pili, an unbeaten French champion.

David Finnegan, 55, who was selling Taylor hats, flags and posters from a stall in her home town of Bray, County Wicklow, this week, said: “Business is tipping away. This is her farewell, everyone wants to be part of it.”

Catherine Hill, 45, had a precious ticket and wanted a Taylor T-shirt for the occasion. “It’s going to be amazing for Katie, the whole country and all women,” she said. “Every young girl now wants to be a boxer or an athlete. It wasn’t like that before.”

Another customer, Denise, 71, bought flags for a pub in Kerry where she planned to watch the bout. “What I love about Katie is that she’s not full of herself. She’s down to earth and still meets up with her friends here. She’s so good with the children.”

Even those with no interest in boxing have been swept up in excitement for an athlete who is adored for blazing a trail in female sports with talent, grit and humility.

Encouraged and trained by her father, Pete, Taylor began sparring as a young girl at a gym so rudimentary it was nicknamed the Tin Can. Women and girls were banned from the ring in Ireland and the UK, so she disguised herself as a boy and signed up to bouts as “K Taylor”.

Father and daughter helped to persuade Irish authorities to lift the ban in 2001, when she was 15, and were instrumental in having women’s boxing added to the Olympic Games. Taylor won gold at London 2012 and went on to headline Madison Square Garden and win an epic trilogy with Amanda Serrano.

McMahon, whose Liberty Boxing gym hosts Taylor during her return visits to Bray, said: “The talent was always there but it was more the dedication. She knew from the get-go what she was going to do. When she comes down to train in the club, the place is packed.”

The last time Croke Park hosted a boxing match was in 1972, when Muhammad Ali fought Alvin Lewis. McMahon said Taylor’s farewell promised to be even more special.

Pili, 29, has won all 12 of her professional fights and holds the IBO world super-lightweight title. She will be no pushover but McMahon said Taylor was determined to add another belt to her titles and go out on a high. “No matter how tough the fight is, Katie always seems to rise to the occasion. If she’s beaten, you’d have to carry her out of there in a box.”

Laney O’Connell, 28, who lives on the estate where Taylor grew up, said she had inspired girls to be fit and active. “When you meet her, she’s completely normal. I don’t think she realises just how big she is,” she said. “And it’s great to see the country represented by a woman instead of a man, especially not McGregor,” she added, referencing the mixed martial artist Conor McGregor.

Anne-Marie McHugh, 58, speaking below a supermarket’s Taylor mural, hoped that Bray’s most famous daughter will enjoy a restful post-boxing life. “It’s time for her to relax,” she said. “She’s earned it.”