Fall guy showing energy around Court One (6)
I believe the answer is:
victim
'fall guy' is the definition.
(thesaurus)
'energy around court one' is the wordplay.
'energy' becomes 'vim' ('vim' can be a synonym of 'energy'**).
'around' means one lot of letters goes inside another.
'court' becomes 'ct'.
'one' becomes 'i' (Roman numeral).
'ct'+'i'='cti'
'vim' placed around 'cti' is 'VICTIM'.
'showing' is the link.
(Other definitions for victim that I've seen before include "Fall guy" , "A prey or sufferer" , "Object of attack" , "Subject of a crime" , "One harmed by crime" .)