Watched sentry and journalist (7)
I believe the answer is:
guarded
'watched' is the definition.
(guarding is a kind of watching)
'sentry and journalist' is the wordplay.
'sentry' becomes 'guard' (I've seen this before).
'and' means one lot of letters go next to another.
'journalist' becomes 'ed' (short for editor).
'guard'+'ed'='GUARDED'
(Other definitions for guarded that I've seen before include "Cautious; watched over" , "Kept watch over" , "Protected from a drudge" , "offered protection" , "Protected, defended" .)