Tech billionaire Mike Cannon-Brookes has taken a 25 per cent stake in Australian rugby league side South Sydney, joining Hollywood luminary Russell Crowe and casino titan James Packer as co-owners, the club said on Monday.

The Australian co-founder of global software giant Atlassian said he was “excited and humbled” to be involved with the Rabbitohs, who were beaten in the National Rugby League grand final last month.

“The South Sydney Rabbitohs are special,” said Cannon-Brookes.

“Not only are we the oldest, loudest and proudest – we are an organisation people truly, deeply care about.

“I’m looking forward to partnering with Russell and James and bringing what I can to the table to help the club grow to even greater heights,” he added.

Cannon-Brookes co-founded Atlassian in 2001 with Scott Farquhar and it has since become one of the world’s biggest collaborative software firms, making the pair among Australia’s richest people.

Last year, he took a minority stake in NBA franchise Utah Jazz.

“This is a very strong move for the club,” said “Gladiator” star Crowe, who bought into the Rabbitohs in 2006.

“Mike understands the resonance of sport in Australia, and James and I welcome his input going forward in keeping South Sydney ahead of the curve, and a game leading organisation, on and off the field.”

The trio will own 75 per cent of the side, with the rest being held by members.

Cannon-Brookes acquired his stake from Crowe and Packer.