It is not difficult to imagine Brad Thorn as a character in a spaghetti western; the good guy, of course. He ambles into the room at the New Zealand hotel in Cardiff, eyes slightly hooded, features craggy, offering a passable imitation of Clint Eastwood in his prime. He looks like a man of deeds rather than words. He is a man you want on your side.

Speaking to him only reinforces the image. His voice sounds like it had its origins in a bottle of bourbon when, in fact, his throat has been smashed too many times by high tackles in the unforgiving world of Australian rugby league. “They're not so hot on the high shots as they are in rugby,” he said by way of explanation. “Believe me, I didn't always sound like this.” He laughs a deep, rasping laugh.

It soon transpires that there is also another dimension to the 33-year-old who has won 22 international caps since 2003. Yes, he is tough - his role in the team as a no-nonsense lock forward demands that he is - but he also turns out to be gentle, reflective and inspiring, a man who, without wishing to sound too hackneyed, radiates goodness and confidence and who is proud to admit that, as a born-again Christian, his life has been turned around.

It was not always so. Born in New Zealand, he moved to Brisbane with his family at the age of 9 and in his professional career has switched twice between league with the Broncos and the Kangaroos and union with Canterbury and the All Blacks. Not that long ago he was a hell-raiser, a womaniser and heavy drinker who, despite making the Australia national rugby league team by the age of 22 with all the supposed perks that such status brought, felt empty and unfulfilled.

Then, on a tour to Great Britain in 1997-98 and with the help of Jason Stevens, a fellow Kangaroos front-row forward, he saw the light. “Jason stood out from the rest of the team,” Thorn said. “On tour we would cut loose and he didn't. I talked to him quite a bit. When you are in a group, everyone says you are weak to not go on the beers, weak if you haven't slept with a woman. It's the opposite. Character is involved.

“I do feel now I have purpose, believe there is a God that loves me. I want be a good father and husband and in a footy context give my best.”

He draws inspiration, too, from the God-fearing Polynesians in the squad. “What's great about the Islanders is they haven't forgotten about God while Western society has. Before I play I say a simple prayer, honouring God through the way I play, 100 per cent aggression and physicality but showing respect to your opponent afterwards whether I win or lose,” Thorn, who went six years without a drink but now has the occasional beer, said. “I am very clear that I am not perfect and I never will be.”

Is there not a contradiction in there somewhere? “God made me a physical child,” he said. “Christ to me is a man's man. On the cross all the disciples fled and people mocked and taunted him. Crucifixion is pretty brutal. He sucked it up and took it. There was nothing fluffy about that. He is my role model.”

After joining Canterbury in 2001, he took a year out in 2002 to “travel, chill and marry”. A year later he played in the World Cup, then returned to the Broncos and was due to finish his career in English rugby league but a contract that did not offer him and his young family sufficient security plus the lure of a last crack with the Crusaders persuaded him to return to the All Blacks fold. He is glad he did.

“Not since Sean Fitzpatrick's era have I seen a [New Zealand] team able to win games ugly like we have been able to do,” Thorn said. “We saw that, for example, in Limerick [against Munster last Tuesday]. We have had our backs against the wall this year in Auckland, Brisbane and Hong Kong and come through. There's character in this team. It is a special thing to have and we'll see where it takes us.” To a grand slam? “We'll see. All I can say is I am in heaven at the moment with my footy. I love it.” He says it without irony.