If it is a force spell directly deflecting the sword (like an instant TK affect) then it most certainly should have an RR. If you want to heat metal on someone's armour that is an RR; if you want to magically disarm someone, that is an RR. You are directly changing someone's action, interacting with their "aura". As to the deflect part of the spell, moving the arrow before launch would be easier, it is difficult to even see an individual arrow in flight; but quite easy to see someone aiming a bow and knocked arrow at you...
Ahhhh the dark path of common sense is in the way again!!!!
Seriously, with straight game mechanics and not too worried about "reality" and seeing as some people think it is an OP spell; making it an RR would add balance.