Hand in face

[bossref]

An opponent can always use his hands and arms
to DISTRTACT, but not to BLIND (obscure vision).
To put hands directly over the eyes of an opponent
with or without the ball is unsporting.

Sometimes defenders will "faceguard" by putting
hands in the shooter's eyes, who now cannot see.
I suggest that you warn once and then penalize
the same type of act, after the warning with a T.