Slob, we agree, adjusted to hard work (5,6)
I believe the answer is:
elbow grease
'hard work' is the definition.
('elbow grease' can be a synonym of 'hard work')
'slob we agree adjusted' is the wordplay.
'adjusted' indicates anagramming the letters.
'slob'+'we'+'agree'='slobweagree'
'slobweagree' anagrammed gives 'ELBOW-GREASE'.
'to' is the link.
(Other definitions for elbow grease that I've seen before include "Vigorous physical labour involving hard rubbing" , "Hard physical work (informal)" , "Vigorous physical effort" , "Hard physical effort" , "Hard rubbing (colloq.)" .)