So jax vs nasus.

I don't really play jax too much bit i used to play him back when i first started playing the game. he was the very first champion i ever played and i loved him but anyways before i get more off topic. I was playing jax vs nasus and i saw that nasus q's bonus damage goes through. How is that physically possible? How can the bonus dmg go through if the auto wasn't completed. It was dodged right? So that means he negates the auto attack and the BONUS Q damage cant go through, but by your logic the auto doesn't even have to be completed because according to the game jax doesn't actually dodge an on hit effect ability. FIx this please. Nasus doesn't have too many counters already He jus thas to farm thats about it.