Can you hit the head/neck of zombies but fail to surpass AR?

[Axelmania]

Pg 37 indicates that you need to roll a 17-20 (a 20% chance) to hit the neck or head.

It doesn't say anything about the AR 14 no longer applying though, so what would happen if penalties modified your roll to be lower than that?

For example, if I roll a 19 to hit, a -10 from blindness would make that a 9 to hit, which is enough to hit a zombie, but not enough to surpass their AR.