Fight using pole (4)
I believe the answer is:
spar
I believe this is a double definition.
'fight' is the first definition.
(sparring is a kind of fighting)
'pole' is the second definition.
(spar is a kind of pole)
'using' acts as a link.
(Other definitions for spar that I've seen before include "Sticks" , "Mineral; plane's wing beam" , "microcrystalline mineral?" , "Box - mineral - rod" , "quarrel" .)