Nisbett, who has been broadcasting for 48 years and has commentated on around 283 tests, said the game has changed a lot in his time. You used to be able to kick the ball out on the full from anywhere and players weren't allowed to be lifted in a line out - you had to jump. But one of the biggest changes was when the game was made professional in 1996.
"When I first started they were amateur, they came out of farms and offices.
"The All Blacks I first dealt with had to drive their tractors or put on suits and go to work... Their skill level is probably higher now playing full time.
"It's a better game now, a far more physical game and faster game there's no doubt about that."
While hooker Dane Coles is Nisbett's favourite current player because they hail from the same rugby club, Christian Cullen gets the honour of being Nisbett's all time top for his "staggering ability" in his 1996 to 2003 All Black career.
"He [Cullen] just had all the skills, he had the pace, anticipation, ability to back up and he was a try scorer."
Despite getting a great view from the commentator's box Nisbett spends most of the game with his eyes glued to the monitor to keep his commentary relevant for those not at the game.
"Otherwise you end up talking about things people can't see at home. It's far better to reflect what people see in their lounges."
He said he does all his preparation the day before, that way on he's free to focus on the game itself. He'll spend hours memorising facts and figures and then only use a fraction of what he's learnt. He said it comes in handy if someone gets hurt and he needs to fill in time.
"But I try not to bombard the audience with too many of them [facts], the game itself is what really matters."
Despite the preparation, not a game goes by where he doesn't make a mistake. Nisbett said the pace of the game and the way jerseys can be obscured means it's very easy to call the player by the wrong name. He dreads doing it when someone scores a try as he has to relive his mistake on the highlights reel.
The hotly contested 1996 South Africa win is one of Nisbett's career highlights as the All Blacks had never beaten the Springboks in a full-scale test series in South Africa.
"We'd never been able to crack it.
"It was one of the last tours ever made there. It was important to get that out of the way when we did."
Nisbett said any number of people could replace coach Steve Hansen when he eventually steps down. The obvious one is Ian Foster but Jamie Joseph, Warren Gatland or Joe Schmidt could also be contenders. There are some Kiwi coaches doing great things overseas, he said.
"We've got coaches who are around the world having success. Whoever takes over the All Blacks will have pretty good credentials."
Nisbett is set to comment on the All Blacks vs Australia from 7pm on SKY Sport 1 tonight. Prior to this the women's Black Ferns are also playing Australia at 4.45pm.
