Ace group performing in ditch (7)
I believe the answer is:
abandon
'ditch' is the definition.
(I've seen this in another clue)
'ace group performing' is the wordplay.
'ace' becomes 'a' (abbreviation).
'group' becomes 'band' (band can mean a group of people).
'performing' becomes 'on' (as in being on stage).
'a'+'band'+'on'='ABANDON'
'in' is the link.
(Other definitions for abandon that I've seen before include "Leave high and dry" , "Desert; intemperance" , "Forsake, leave behind" , "scrap" , "Leave (a place) for ever" .)