On stage (3)
I believe the answer is:
leg
This clue is a double definition.
'on' is the first definition.
(cricket term)
'stage' is the second definition.
(a leg is a stage of a competition)
(Other definitions for leg that I've seen before include "Stage (of race)" , "Section of journey; limb" , "Limb; stage" , "Run < on" , "Projecting support for chair or table" .)