Runs excellent competition (4)
I believe the answer is:
race
'competition' is the definition.
(I've seen this before)
'runs excellent' is the wordplay.
'runs' becomes 'r' (cricket abbreviation).
'excellent' becomes 'ace' (I've seen this before).
'r'+'ace'='RACE'
(Other definitions for race that I've seen before include "eg The Oaks" , "Run, dash" , "water" , "compete to come first" , "Run; nation" .)