Being the striker's target, girl has nothing to say (9)
I believe the answer is:
goalmouth
'being the striker's target girl has nothing to say' is the definition.
I can't tell whether this definition defines the answer.
'target girl has nothing to say' is the wordplay.
'target girl' becomes 'gal' (I can't explain this - if you can you should believe this answer much more).
'has' indicates putting letters inside.
'nothing' becomes 'O' (looks like zero - 0).
'to say' becomes 'mouth' (I've seen this in other clues).
'gal' enclosing 'o' is 'goal'.
'goal'+'mouth'='GOALMOUTH'
Can you help me to learn more?
(Other definitions for goalmouth that I've seen before include "patch often worn on pitch" , "keeper's area" , "strikers aiming to get there" , "that keeper guards" .)