Redo short haircut for swimmer (3,6)
I believe the answer is:
red mullet
'swimmer' is the definition.
(red mullet is a kind of fish)
'redo short haircut' is the wordplay.
'short' means to remove the last letter.
'haircut' becomes 'mullet' (hair style).
'redo' with its last letter removed is 'red'.
'red'+'mullet'='RED MULLET'
'for' is the link.
(Other definitions for red mullet that I've seen before include "There's something fishy" , "Tasty swimmer" , "Brightly coloured food fish" , "Fish -- dull meter (anag)" , "one's gathered in net" .)