The turnaround has not only seen him become the face of one of Australia's oldest league clubs but also an evangelist for the sport itself. And he's hatching plans to stage games in Las Vegas.
It hasn't been a smooth ride.
In 1999, seven years before Crowe's takeover, Souths had been thrown out of the league for becoming financially unviable. Even after street protests and a successful court battle to reclaim the team's place for the 2002 season, results on the field eluded them. They were last in 2003, 2004 and 2006, and were seen as the laughing stock of the competition.
Souths fan Kristina Keneally, the former New South Wales state premier, whose electorate included Souths, met Crowe in her office as he prepared to buy the club.
"My greatest fear was the club was going to just fall in on itself," Keneally says. "But he worked with the local community brilliantly. He didn't behave like a movie star. He behaved like a guy who was from South Sydney. Russell Crowe is not just a remarkable actor - he's a remarkable politician."
Crowe and his business partner Peter Holmes Court bought 75 per cent of the club. Then Crowe set out to transform his group of losers into winners.
He commissioned a slab-size tome entitled The Book of Feuds to chronicle the club's century-old local rivalries and stir up his players. A 2007 documentary, South Side Story, which follows the early days of Crowe's ownership, shows the actor blowing dust from the pages of the book and reading passages to the players: "Our blood should boil every time we run on to play. It's time to spoil the party."
Off the field, Crowe dressed the squad in Armani suits ("It is important to dress for success"). He redesigned club merchandise and ran his eye over the labelling ("The 'O' is out of line"). For some games, he replaced the club's emblem - a fluffy white bunny - with a black rabbit ("Black rabbits eat people").
And Crowe didn't hesitate to use his acting chops to bring the world's best players to Souths.
In the 2013 documentary Slammin' Sam: The Sam Burgess Story, Crowe tells how in 2009 he won over Burgess, who was then playing for Bradford. During a break from filming Robin Hood in England, Crowe, the 116kg forward and his mother chatted for hours in the actor's trailer.
"It was like stories in front of the fireside," says Crowe. "If you put 20 cents in me and ask me to talk about South Sydney, I'll play all night."
Burgess moved to Souths and was central to the club's victorious 2014 premiership campaign. He played most of the grand final with a broken eye socket. His three brothers joined him on the club, as did Australian international Greg Inglis.
Souths was created a little more than a decade after rugby league was born in northern England out of a dispute over player payments.
The game glued together the community around the club's inner-city base in Redfern, a centre of aboriginal culture. In the early years, players were local residents, and among working families, loyalty was handed down through each generation. Crowe's challenge was to carry these supporters with him.
Bob Berry, 73, who watched his first Rabbitohs match as a child in 1949, has four generations of fans in his family. "The great success that Russell Crowe's had is, he has recognised that it was the people's team."
Crowe turned to those people to help repair his club's finances. Before the 2010 season, he challenged supporters to prove their loyalty by paying up for membership. Last month, Souths set a new league membership record.
Crowe, with a new partner in the club - casino billionaire James Packer - is spying new opportunities following the World Club Challenge win and last month suggested taking top Australian and English teams and playing a new championship in Las Vegas to generate club revenue and create a TV spectacle. That's a big ask in a country largely unfamiliar with rugby league.
"He's going to have to get people who previously had just gotten used to union to buy into this different variation," says Rick Burton, a sports management professor at Syracuse University in New York. "Still, with a big enough marketing budget, there's a chance it could succeed."
- Bloomberg
