Skilled worker in boat's crew (9)
I believe the answer is:
craftsman
'skilled worker' is the definition.
(craftsman is a kind of skilled worker)
'boat's crew' is the wordplay.
'boat's' becomes 'craft's' (boat is a type of craft).
'crew' becomes 'man' (I've seen this before).
'crafts'+'man'='CRAFTSMAN'
'in' acts as a link.
(Other definitions for craftsman that I've seen before include "Carpenter, say" , "Skilled worker" , "Artisan" , "Expert" .)