The All Blacks' last major challenge this season against Ireland — sorry Italy you're not in the same league — has more dimensions than a Rubik's Cube.
Whichever way you twist and rework your ideas about this blockbuster in Dublin, one thing is clear about the team choices.
Injury has bitten into both sides but on this count the All Blacks have made inroads with the forced absence of Sonny Bill Williams, while Ireland have been unable to pick Conor Murray, who drives much of their play from halfback.
Ireland have risen to the second-rated side in the world through the discipline instilled by coach Joe Schmidt and his offsiders, while that cohesion has been driven on the park by Murray with his skilled tactical clarity at the hub of the team.
Box kicks, deft passes to runners, calling on defenders, covering tackles — the Irish halfback nails all areas and his loss will nip into his side's purpose.