Try to back clubs (4)
I believe the answer is:
bats
'clubs' is the definition.
(bat is a kind of club)
'try to back' is the wordplay.
'try' becomes 'stab' (I've seen this before).
'to back' says the letters should be written in reverse.
'stab' reversed gives 'BATS'.
(Other definitions for bats that I've seen before include "Lunatic" , "Crazy - mammals" , "bananas" , "Cuckoo" , "Hutton and Gilligan" .)