A plucky sport? (4)
I believe the answer is:
game
This clue is a double definition.
'a plucky' is the first definition.
(both can mean enthusiastic or willing)
'sport?' is the second definition.
(I've seen this before)
(Other definitions for game that I've seen before include "Hobbling" , "What might get hung" , "Creatures killed for sport" , "Final declaration of tennis result - . . . ., set and match" , "Hunted wildlife" .)