It's pretty much Blades of Glory but in the pool: a couple of old pro-swimmers searching for a comeback, who defeat tradition, prejudice and ultimately the Russians (of course) to win the world championships in a sport that – until last year – did not even exist.

But in this case it's not like Will Ferrell and Jon Heder exploiting a loophole in a Hollywood figure-skating comedy, but a deliberate (and, many would argue, overdue) change in the rules to allow mixed gender duets in synchronised swimming.

At the centre of it all is 36-year-old Bill May. Once banned from the sport because he is a man, he came out of semi-retirement to compete with fellow American Christina Jones at this year's world championship in Kazan, Russia.

The tectonic plates of the swimming world shifted late last year when the global peak body – the Federation Internationale de Nation (FINA) – voted to allow mixed-sex synchronised swimming at its premiere event.

May, who had competed in designated mixed events over the years, was pleased to have finally been granted permission to compete for a world title.

"I'm still in disbelief that this dream, that was tucked away years ago, is becoming a reality," he said on Facebook ahead of the championships.

Jones, 27, competed at the 2008 Olympics in Beijing – something May was unable to do and which would still be impossible, as mixed-gender competitions are not allowed at the Olympic Games. Both had kept themselves active in recent years on the circus circuit, performing 10 shows a week with Cirque du Soleil in Las Vegas.

At Kazan, their scissor-kicking routine defeated Russians Aleksandr Maltsev and Darina Valitova by 88.5108 points to 88.2986. Maltsev, Russia's only male synchronised swimmer, was not happy with the results.

"We were underscored, and all others were clearly overscored," he said. "That's bitter, we are upset."

Indeed, Russia – which dominates synchronised swimming – has been less than thrilled about the whole concept of mixed-gender events.

Sports Minister Vitaly Mutko labelled the idea a mistake that betrayed the "purely feminine sport", suggesting it may have been a deliberate conspiracy by Russia's rivals.

"Evidently, some kind of group of countries has pushed this through," he reportedly said at the time.

And Olympic silver medallist Evgeny Korotyshkin told Russian media last year that he might "cry" at the sight of a male synchronised swimmer's "hairy legs poking out of the pool".

The liberalisation of synchronised swimming rules has been a long journey; one in which May has been intimately involved. He won the duet event at the US championships in 1998, swimming with Kristina Lum. The duo then won a silver medal at that year's Goodwill Games.

But he faced opposition from the several bureaucracies, including the US Synchronised Swimming Federation, which failed to push for his inclusion at the 2004 Olympics in Athens.

Veteran swimming coach and administrator Ginny Jasontek ruled point blank: "We cannot allow men in a women's sport."

The FINA decision indicates attitudes have changed somewhat since that time. But the biggest reform remains elusive – inclusion at the summer Olympics. May and Jones hope it will happen in time for them to continue their comeback tour.

"This was a real big test event to see what type of response the world would give this and I think the world has given a great response," May said. "Someday it will be there."

– with agencies