Run in preliminary contest, displaying courage (5)
I believe the answer is:
heart
'courage' is the definition.
(I know that heart is a type of courage)
'run in preliminary contest' is the wordplay.
'run' becomes 'r' (cricket abbreviation).
'in' is an insertion indicator.
'preliminary contest' becomes 'heat' (qualifying stage in a sports contest).
'r' inserted within 'heat' is 'HEART'.
'displaying' acts as a link.
(Other definitions for heart that I've seen before include "Centre; core" , "See 22" , "Pumping organ" , "Cardiac courage" , "It beats" .)