Nothing in season, Augusta having exported American plays (3,1,7)
I believe the answer is:
not a sausage
'nothing' is the definition.
('not a sausage' can informally mean nothing)
'season augusta having exported american plays' is the wordplay.
I cannot quite see how this works, but
'season' could be 'age' (I've seen this in another clue) and 'age' is present in the answer.
'american' could be 'us' (abbreviation for United States) and 'us' is found within the answer.
This explanation may well be incorrect...
'in' acts as a link.
(Other definitions for not a sausage that I've seen before include "diddly-squat" , "Absolutely nothing" , "zip" , "Alternative to banger, maybe" , "Zilch (colloquial)" .)