A dog caught Stan's partner (6)
I believe the answer is:
collie
'a dog' is the definition.
(collie is a kind of dog)
'caught stan's partner' is the wordplay.
'caught' becomes 'c' (cricket abbreviation).
'stan's partner' becomes 'ollie' (Ollie Hardy, comedy partner of Stan Laurel).
'c'+'ollie'='COLLIE'
(Other definitions for collie that I've seen before include "Working animal" , "Type of sheepdog" , "Sheep-herding dog" , "Long-haired intelligent dog" , "Silky-coated sheepdog" .)