Poet's written about love for stage (6)
I believe the answer is:
boards
'stage' is the definition.
(thesaurus)
'poet's written about love' is the wordplay.
'poet's' becomes 'bards' (bard is a kind of poet).
'written about' is an insertion indicator.
'love' becomes 'o' (In tennis, 'love' means 'zero').
'bards' going around 'o' is 'BOARDS'.
'for' acts as a link.
(Other definitions for boards that I've seen before include "Tread them in the theatre" , "Theatre stages" , "Gets on; the stage (colloq.)" , "Long flat pieces of wood" , "Adsorb (anag)" .)