Rugby League World Cup: Dwayne 'The Rock' Johnson backs Toa Samoa against Australia in Old Trafford final

American actor Dwayne 'The Rock' Johnson has thrown his substantial support behind his "usos", as Toa Samoa prepare to make history against Australia in the Rugby League World Cup final on Sunday.

After losing to the same team by 54 points in their tournament opener, Samoa shocked hosts England in the semis to book a showdown with the champion Kangaroos at Old Trafford - their first appearance in a World Cup final.

Their achievement has not gone unnoticed by one of the world's most influential Samoans.

"I am delivering this message with boundless love, and boundless reverence and respect... and boundless pride," Johnson said on Twitter. "For my boys, my usos, the Toa Samoa rugby team are going to the men's final of the Rugby League World Cup.

"This is a big deal - they are making history in the world of sports, the world of rugby... this is the first time our island, our country, our culture of Samoa has ever gone to the finals for any sport.

"They are making history and I could not be more proud of them."

Johnson, 50, has his own sporting pedigree, winning a US college football title at University of Miami and then rising to worldwide prominence as a professional wrestler, before breaking into movies.

Most recently, he entered the Marvel Universe as onscreen superhero Black Adam.

Johnson has Irish and Black Nova Scotia heritage through his father, while his mother is Samoan.

Toa Samoa's emergence as a rugby league superpower at the World Cup has sent shock waves around the world, but they are still $6.50 outsiders at the NZ TAB, with Australia paying $1.10.

Join us at 5am Sunday for live updates of the Toa Samoa v Australia Rugby League World Cup final