Heated fighting before start of match (4)
I believe the answer is:
warm
'heated' is the definition.
(thesaurus)
'fighting before start of match' is the wordplay.
'fighting' becomes 'war'.
'before' is a charade indicator (letters next to each other).
'start of' says to take the initial letters.
The first letter of 'match' is 'm'.
'war'+'m'='WARM'
(Other definitions for warm that I've seen before include "Friendly" , "Welcoming - getting close!" , "Approaching target" , "Affectionate - balmy" , "showing enthusiasm" .)