Go and change (4)
I believe the answer is:
turn
I believe this clue is a double definition.
'go' is the first definition.
(as in one's go or turn in a game)
'change' is the second definition.
(I know that turn is a type of change of course)
'and' is the link.
(Other definitions for turn that I've seen before include "revolutionary act" , "Twist; go" , "Go off - performance" , "Revolution by runt" , "Shock - move - change course" .)