Ditch bar, Spooner advises sailor (7)
I believe the answer is:
boatman
'sailor' is the definition.
(I've seen this before)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for boatman that I've seen before include "One having row with" , "Water transport provider" , "Fellow with craft" , "He may have a smack" , "One in charge of a small vessel" .)