The Bay of Plenty's Sam Cane got a cuddle from his mum and a big vote of confidence from his coach and team-mates after being handed the All Blacks' captaincy for their Rugby World Cup pool match against Namibia.

Cane says his initial reaction was one of shock when coach Steve Hansen told him on Wednesday he'd be taking the reins from Richie McCaw at London's Olympic Park on Friday.

New All Blacks captain Sam Cane talks to the media. Photo: Peter Meecham/Stuff.

'I was hoping with a short turnaround it would be great to get a start, then he said you will be starting and also be captain. It took me back a bit,” admits the 23-year-old.

In his 26th test, Cane will become the fifth-youngest player to captain the All Blacks and he said sharing the news with his deer-farming parents Malcolm and Kathy had made for a special day.

'It's extremely special to become an All Black for the first time, but to lead your country out is something that stands above that,” says Cane.

'I was quite fortunate that I had a bit of family come over. Mum and dad were at the game against Argentina and we had a bit of time off this morning, so I took them out for breakfast and told them in person, which was pretty nice.

'They were much the same as me when I first got told [surprised], but they were very, very proud obviously.

'Mum gave me a cuddle and it was nice to share it with them in person.” The previous night McCaw had dropped by to provide a quick word of congratulations and support.

It must have been an odd moment for Cane, who has toiled away as McCaw's deputy since making his debut in 2012, with just 11 starts in 26 tests since.

At the Olympic Park on Friday, the kid from Reporoa will wear the All Blacks' No. 7 and McCaw, with a higher number on his back, will wear a broad smile.

The jersey McCaw has cherished for all but a handful of his 143 tests will be in good hands when he hangs up his boots.

Coach Steve Hansen says he'd be 'bulls****ing” if he said he'd fingered Cane as a future All Blacks captain from the moment he saw him, but he had no doubt after watching him over the past four seasons.

'I've never believed leaders are born, that's a myth they are made. It starts with playing well. You play well enough you get selected more and more,” Hansen said.

'The most important part of leadership is playing well and he does that good. I don't think he's ever played poorly for the All Blacks.”

Cane had faced a tough time after being brought into the team as an unheralded 20-year-old and the way he handled his role as McCaw's back up since then said a lot about his character.

'When he first came in he was only a baby,” Hansen says of Cane.

'He coped with all the criticism early in his career from the media and some fans because they didn't know him or who he was.

'He never deviated off the game plan. He worked hard and trained hard. That's a sign of leadership when you can stay on task when everything around you is imploding.

'Sam's time around Richie has been good in that he's had to think about the whole team not just himself.”

Cane's previous captaincy experience has included his school first XV and the Chiefs in Super Rugby, where team-mate Liam Messam says he'd always seemed older than he was.

'I'm very happy for my little mate,” says Liam. 'I remember this kid who was 17 rocking up to Chiefs training looking like he was 30.

'He was a great kid, he was strong in the gym and he was fit. He got stuck into training with the Chiefs and he's got a lot more confident as the years have gone by.”