Rascal showing regret about own goal (5)
I believe the answer is:
rogue
'rascal' is the definition.
(both can mean a scoundrel)
'regret about own goal' is the wordplay.
'regret' becomes 'rue' (to rue something is to regret it).
'about' is an insertion indicator.
'own goal' becomes 'OG' (football abbreviation).
'rue' going around 'og' is 'ROGUE'.
'showing' acts as a link.
(Other definitions for rogue that I've seen before include "Wild animal driven away from herd" , "Miscreant" , "Fraud" , "Profligate" , "A dishonest or unprincipled person" .)