Deserve to bust docker (9)
I believe the answer is:
stevedore
'docker' is the definition.
('stevedore' can be a synonym of 'docker')
'deserve to bust' is the wordplay.
'bust' is an anagram indicator.
'deserve'+'to'='deserveto'
'deserveto' anagrammed gives 'STEVEDORE'.
(Other definitions for stevedore that I've seen before include "he'll have loads on board" , "Dock worker" , "Hold worker" , "Worker who loads and unloads ships" , "Unloader of shipping vessels" .)