Shambles as Rooney originally included in side (5)
I believe the answer is:
farce
'shambles' is the definition.
'rooney originally included in side' is the wordplay.
'originally' indicates taking the first letters.
'included in' is an insertion indicator.
'side' becomes 'face' (face is a kind of side).
The initial letter of 'rooney' is 'r'.
'r' put within 'face' is 'FARCE'.
'as' acts as a link.
(Other definitions for farce that I've seen before include "Absurd drama" , "A ridiculous comedy or absurd proceedings" , "Absurd event; comedy" , "Ludicrous comedy" , "Absurd proceedings, perhaps in play" .)