Cricketer at the crease (7)
I believe the answer is:
batsman
'cricketer at the crease' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for batsman that I've seen before include "Player at crease" , "one of two on the field" , "He's either in or he's out!" , "Grace, for example" , "One at the crease" .)