The respective midfields share the same desire to attack - to breach the gainline through a combination of direct running, timing and angle selection. Ma'a Nonu and Conrad Smith have different body shapes to Damian de Allende and Jesse Kriel but essentially are there to do the same thing - get their team over the gainline and into space.
Handrie Pollard is a running five-eighth with an accurate kicking game. Dan Carter is a running five-eighth with an accurate kicking game.
The two loose trios are frighteningly similar - big, physical men with mobility, aerial and ball skills. They all compete at the breakdown, they all tackle and the two No 8s - Kieran Read and Duane Vermeulen have the ability to pull off the outrageous.
All four locks are young, rugged and the epitome of the modern tight forward. They have the athleticism to be pseudo loose forwards, but the size and mindset to be locks first and foremost.
And again, the respective front-rows attend to the core jobs of scrummaging and lifting first, but do much more. Especially the two hookers - both Dane Coles and Bismarck du Plessis can be damaging in different ways with ball in hand.
It seems curious, then, given the skills and abilities of the respective players aren't so different, that the rugby they produce is. And the key to understanding why sits with the respective halfbacks.
The Boks have the vastly experienced Fourie du Preez behind their pack and he's the beating heart of their side. He is their tactical director - he determines the tempo they play at and he's a halfback who always has his head up and works his options.
When the Bok forwards are on top, du Preez is in his element: using his tactical kicking, short side sniping and pop passing to keep the pressure on the opposition.
Aaron Smith is not that sort of player. He's a clear the ball and run halfback. That's his job - to get his hands on the ball and move it as quickly and accurately as he can. He kicks well from the base and chooses his times to run cleverly, but it's his speed to the breakdown and then speed of clearance that allows the All Blacks to play at such pace and with such width.
And the two halfbacks are shaping as the men who will make this semifinal a game of contrast styles and ultimately determine the outcome. If the Bok forwards are on top, du Preez will be a man not loved by New Zealanders. He'll throw salt in open wounds, turn the All Blacks, twist them and then send big runners smashing into them.
But if there is parity in the forward exchanges, the speed of Smith and his endless ability to keep the ball firing across the field will see the game played at a pace which may be too much for the bigger South Africans.
The Boks may not be quite fit enough to cope and the wider the All Blacks play, the more their ball skills come into the equation.
