Doctor grabbed by porter, perhaps for leisurely stroll (5)
I believe the answer is:
amble
'for leisurely stroll' is the definition.
(I've seen this in another clue)
'doctor grabbed by porter' is the wordplay.
'doctor' becomes 'mb' (Bachelor of Medicine).
'grabbed by' indicates putting letters inside (inserted letters are grabbed inside).
'porter' becomes 'ale' (type of beer).
'mb' put within 'ale' is 'AMBLE'.
'perhaps' is the link.
(Other definitions for amble that I've seen before include "Move at an easy pace" , "Stroll, saunter" , "Make slow progress" , "Take leisurely stroll" , "Walk in a leisurely way" .)