The cat, as usual, then wanders in (7)
I believe the answer is:
panther
'the cat' is the definition.
(panther is a kind of cat)
'usual then wanders in' is the wordplay.
'usual' becomes 'par' (par is an average golf score).
'wanders' is an anagram indicator.
'in' indicates putting letters inside.
'then' with letters rearranged gives 'nthe'.
'par' enclosing 'nthe' is 'PANTHER'.
'as' acts as a link.
(Other definitions for panther that I've seen before include "Then rap the large black cat" , "Black leopard" , "Bagheera?" , "big pussycat" , "kind of feline" .)