When you hear the name Red Star Belgrade, you think of the famous 1991 European Cup winners.

You think of Serbia's most successful football side with 30 titles, the grand Rajko Mitic Stadium and Red Star Belgrade's basketball team from the famous multi-sports club.

Belgrade is a city steeped in history and known for its passion for football and basketball. It is not synonymous with rugby league. But one Australian is changing that.

Colin Kleyweg is the owner of the fledgling Red Star Belgrade rugby league team, who are unbeaten in the whole Balkan region since November 2018, winning 10 consecutive trophies.

"I met a Serbian lady about 13 years ago," Kleyweg, who also serves as a director of the Rugby League European Federation, told Stats Perform. "We got married about 11 years ago and we started businesses together in Serbia because we run an engineering consultancy business here in Australia. So, we set it up in Belgrade as well about nine years ago.

"When we were there, we wanted to start giving back to the community and we found rugby league. I love it and my wife has fallen in love with it too. So, we started helping the Serbian federation first, then in January 2017 we met the guys at Red Star and they basically said, 'What would you think about doing something?' And we said yes."

Led by Australian former NRL head coach Phil Economidis, Red Star are making a splash. A member of the Red Star Sports Society, the rugby league team were recognised as the most successful club within the entity this year with 13 titles since 2014. They also played in the Challenge Cup in 2019.

In a city with a strong thirst for football and basketball, rugby league is a new concept but Kleyweg is still dreaming big.

He added: "The issue is, it's an unheard sport. Every time I bring people to it, of Serbian descent, and they sit next to me and I tell them what's happening, they're riveted. They absolutely love it. They've just said this sport is perfect for the Serbian psyche and the Serbian body type: the prototype centres and running backrowers."

Red Star had intended to apply to the Rugby Football League for a place in League 1 – the third tier in the United Kingdom – possibly as soon as 2021. However, the coronavirus pandemic scuppered those plans, with Kleyweg now focusing on forming a European club competition.

"We have to play the right teams," Kleyweg said. "Luckily I'm also on the board of the European Federation. A year or so ago, I was put in charge of a working group to examine a professional European rugby league club competition. My dream is to have a much smaller version of the Euro League basketball."

So, what is the standard of rugby league like in Serbia?

"They are technically very good, and they have the body shape and mass for it," Kleyweg said. "The mentality, too. They're already punching well above their weight. In any sport, you need people to be able to coach and to teach the intricacies of the game. A lot of the boys, they don't start playing until they hear about it. We have a very small number of men who were trained as juniors. From five or six clubs, you really have a pool of about 20 players that are capable of playing against English opposition.

"One of the best things I ever did was bringing Phil, having NRL experience as well – they just soak up everything. I've been slowly integrating players into full-time structures. Instead of training once or twice a week because a lot of them have jobs, they can get proper sleep, better nutrition."

There is a strong Australian influence on the club. Kleyweg, though, has since steered away from an influx of Aussie and international players in an attempt to improve the standard of Serbians.

"I brought over some Aussies previously. I wanted the players to see the level and the professionalism needed," he continued. "When I did bring over internationals, we started slaughtering every team we played. In recent years, we win on average by 60 points, so there's no need for that. I've taken out those players because we don't need to do that.

"Partizan [neighbours and bitter rivals] are now getting much, much stronger, which is good. They're building a nice rivalry with us, which is standard. This year, we beat them with a very Serbian-only team, which I'm proud of. We are the first Serbian side to beat English opposition. That's part of the plan. I want to teach the boys the right mental approach to it. Serbians can be a bit like the French: when they're losing, they can drop their heads and start to perform poorly. We've had that in the national team. I want the players to develop a resilience. I want to see them in a match where you should really lose but somehow find a way to win."