'Kick the bastard': All Black coach Steve Hansen's quirky message to Mo'unga before match-winning kick

Tied up at 30-30 with time up on the clock in front of thousands of desperate screaming South African fans, Richie Mo'unga etched his way into Kiwis' hearts by slotting the winning conversion to cap off one of the best comeback victories you'll see.

It was a moment that'll be remembered by All Blacks fans for years to come, and a glimpse of what Mo'unga can bring to the 10 jersey come crunch time.

With nerves no doubt running through the player's body, one journalist at the post-match press conference asked Kieran Read what message he gave Mo'unga before kicking the vital conversion.

"Kieran, did you have a message for Richie just before that winning kick?" one member of the New Zealand media asked.

But it was Steve Hansen who swooped in to give a typically dry response.

"Kick the bastard," he joked.

[All Blacks aftermath: The Houdini on the Highveld - All you need to know about ABs dramatic comeback]

Meanwhile, on the field, Read revealed he simply told Mo'unga to "take his time".

Hansen's relief was clear during the press conference, taking time to praise his impact subs while tipping his hat to a brutal South African side.

"You're not going to have the momentum for the whole 80 minutes if you're playing against a quality team," Hansen said.

"South Africa had it for a long time but at some point if we kept fronting up, believing we were going to have our turn and then it was a matter of making sure we made the most of our turn.

"It could easily have been one we let go and allowed them to win but they dug in deep and refused to give up. Sometimes if you keep knocking on the door someone will open it and you can come in."

For 65 minutes Rassie Erasmus' vastly-improved Boks dominated, only to fold when the All Blacks finally secured and retained some decent ball.

"South Africa played incredibly well and are probably unlucky not to have won it. We thought we were unlucky not to win in Wellington. So two great test matches which is great for the game."

Hansen quickly dismissed the notion this result would hold a major bearing on his side's opening World Cup test against the Boks next year but did acknowledge its importance in regards to overcoming pressure.

"Everyone gets excited about how this game is going to make a difference at the World Cup. It won't matter a hoot. What it will do is for our young players who haven't been in a situation when they haven't been behind before, they'll put their head on the pillow tonight understanding that [they] don't stop believing.

"For the South Africans it will be don't stop playing. Don't give an inch. Both teams will get plenty out of it from that point of view."