Blues have fitness to see out Castres
Castres Olympique v Leinster
Pierre Antoine, Sunday (KO 1.0 SS3)
It must be true. The work of The Academy, the under-appreciated All-Ireland League and the wonder that is not the British & Irish Cup all combine to get players ready for the Champions Cup.
For when Leinster are fully-armed with their internationals, the next layer are busy working away in far less glamorous places.
For moments like these.
Where would Darragh Fanning be without the AIL? Noel Reid and Michael Bent without the B&I? Further away from where they are.
Sometimes you do have to see it to believe it. Cue Wasps.
Sometimes you have to feel it to believe it. Cue Castres.
The 2013 French champions removed all negative thoughts from their pale imitation of recent years in the Top-14 League where they languish in twelfth to put Harlequins to the pin of their collars at The Stoop.
As Eoin Reddan suggested earlier in the week: "they buck the trend" when it comes to the French.
They are unpredictable and always ready to defend their castle at Stade Pierre-Antoine.
Leinster know this only too well from the shell-shock of going 14-0 down while the scrum was being pulverised there last January.
However, superior conditioning allowed them to battle back for a 29-22 victory to end Castres'18-match unbeaten run at home.
They have to drain Castres of their physical stamina and come on strong in the final quarter.