"I just remember this kid who was 17 rocking up to Chiefs training looking like he was 30; he was a big kid," Cane's Chiefs and All Black team-mate Liam Messam told the media in London this morning.
"He was strong the gym, he was fit and he just got stuck in."
Oh my goodness did he get stuck in, without fear of personal harm or opposing reputations.
And he was a quick study too.
I was fortunate enough to be handling side-line commentary duties at Waikato Stadium when Cane came on the scene.
It was early in his Super Rugby career (2011 rings a bell, the season after his debut against the Lions) and he came on with 9 minutes to go against a South African team (the Stormers maybe ... don't quote me on that).
Within seconds he had the chance for a turn over.
In he went, bending over at the waist to get the ball, creating a massive target for the opposition "cleaners" to aim at.
Let me tell you, they ...did ...not... miss!
Cane was sent careening like he'd been shot out of a cannon.
Play stopped immediately for another infringement and Cane sat there, briefly wide eyed. Then the eyes narrowed and you could see the resolve steeling itself.
The next breakdown, Cane was in there again, this time legs askance, knees bent, backside positioned directly over his heels, hands on ball, body braced, a perfectly positioned immovable ball of Reporoa robustness - whistle - "penalty, not releasing, 19 had all rights to the ball" - turnover to the Chiefs.
He stole another one in that nine minute cameo by the way.
It's also interesting that Sam Cane's never been first choice in his pro rugby career until this year's Super Rugby season.
Prior to that, Cane split reps with Tanerau Latimer at the Chiefs, with the Bay of Plenty veteran preferred to the Bay of Plenty youngster to start in the big games.
But it's what he's done in the All Black jersey that's the most impressive because it's not easy to live in the shadow of greatness.
Think of the number of All Black openside flankers who have been understudy to Richie McCaw during his incomparable career.
None them have handled that situation in the calm, unflappable yet determined manner in which Sam Cane has since he debuted in 2012.
In naming Sam Cane captain this morning coach Steve Hansen said "I don't think he's ever played poorly for the All Blacks and he's got a reasonably tricky job in the team to follow the skipper".
And he's right - mind you he normally is when it comes to his players.
Liam Messam made another great point about his "little mate" becoming captain this morning.
"It's the way he holds himself as a person off the field.
"It's all good doing it on the field but you also have to be a great leader off the field and he does that."
That too is so very true.
He's great with fans, great with media and is very well liked and respected by his team-mates, management and opposing players.
No-one sensed that Sam Cane was going to be an All Black captain.
All we did was watch him as he proved himself worthy and deserving of the honour.
-Radio Sport will bring you Live Commentary of every All Blacks game with Nigel Yalden.
