Coached in art management by journalist (7)
I believe the answer is:
trained
'coached' is the definition.
('train' can be a synonym of 'coach')
'in art management by journalist' is the wordplay.
'management' indicates an anagram.
'by' says to put letters next to each other.
'journalist' becomes 'ed' (short for editor).
'art' anagrammed gives 'tra'.
'in' after 'tra' is 'train'.
'train'+'ed'='TRAINED'
(Other definitions for trained that I've seen before include "Worked out" , "Prepared for a task or career" , "Prepared for race" , "Taught (a skill)" , "Instructed - took aim" .)