In the long history of the Ma'a Nonu-Conrad Smith midfield combination few partnerships have gotten the better of them.
One that did, though, was the Springbok due of Damian de Allende and Jesse Kriel who were the more dynamic, cohesive and penetrative pairing when the All Blacks played South Africa earlier this year.
It was a classic contest of young versus old: of exuberance and youth taking on experience and calm.
Nonu and Smith have faced many similar battles - but at Ellis Park in July, they were outplayed. And what that means in midfield terms is that the Bok due were able to play in front of the gainline.
They were able to create and then exploit space and there were long periods in that test when the All Blacks were clinging on. That's how it is when one midfield is able to ask more questions than the other one can answer.
The All Blacks somehow managed to win, which even they would say was perhaps not quite the right result on balance, but pulled off on the back of their heroic scrambling defence and one brilliant lineout variation that saw Richie McCaw crash over for the winning try.
Inevitably that mini victory for the South African pairing sparked a frisson of concern that the old guard of Nonu and Smith were maybe tiring down the stretch.
A few months out from the World Cup, had age finally caught up with the world record duo? Kriel in particular posed several problems that day - not the least of which was his delayed running on to the ball and astute lines and timing.
He scorched through a hole for a memorable try without a hand being laid on him and it was one of those poignant moments where it was hard not to advance such a scenario into the future.
If the All Blacks met the Springboks in a World Cup semifinal - as always looked possible - would South Africa feel they had the creative advantage in the midfield stakes?
So few teams, if any really, have been able to look at Nonu and Smith since 2008 and feel they are going to come out on top: that they are going to win the little battles that can mean so much in the bigger picture.
De Allende has the footwork and patience to fix the inside defence while Kriel runs sharply into the space that creates. It's a simple but effective formula and has worked for the Boks at this World Cup. Those two have grown their influence and understanding of each other and of test football.
The injury to their talismanic captain Jean de Villiers has perhaps been a blessing rather than a curse as it has allowed coach Heyneke Meyer to stick with De Allende and Kriel - a pairing that was crying out to be picked. With de Villiers fit, the situation would have been delicate.
Without him, it's now troublesome for the All Blacks. Nonu and Smith have been around for long enough to never need reminding of where the dangers lie, but it is no bad thing they have particular reason to be excessively vigilant this week.
"They have been very impressive so far," said Smith of the Bok midfield. "I think individually they are great players and they have formed a great partnership. I was gutted for Jean [de Villiers] obviously - he's the one I have played against more than anyone else.
"I am sure he's still a big influence on the team and helping the guys who are there.
"We are aware of what they do for the team. They are a couple of major strike weapons and they will take a bit of containing.
"I think they played particularly well the last time we played in South Africa and they probably had the wood on Ma'a and I so we know how dangerous they can be. They have carried that all through this World Cup. They get the whole team going forward."
Youth had its day at Ellis Park. But all the statistics show that World Cups are where experience makes its presence felt.
