Last in pub always gets older drinks (9)
I believe the answer is:
'drinks' is the definition.
(I know this)
'last in pub always gets older' is the wordplay.
'last in' indicates one should take the final letters.
'always' becomes 'ever' (synonyms).
'gets older' becomes 'ages' ('age' can be a synonym of 'get older').
The last letter of 'pub' is 'b'.
(Other definitions for beverages that I've seen before include "Vegas beer (anag) - beer etc" , "Drinks" .)