Lets US fans fight (6)
I believe the answer is:
tussle
'fight' is the definition.
(I know that tussle is a more specific form of the action fight)
'lets us fans' is the wordplay.
'fans' is an anagram indicator (I've seen 'fanned' mean this (I've seen this in other clues)).
'lets'+'us'='letsus'
'letsus' is an anagram of 'TUSSLE'.
(Other definitions for tussle that I've seen before include "Skirmish" , "Fight vigorously" , "A struggle or conflict" , "Go at it" , "scrap" .)