Yawned, opening with journalist (5)
I believe the answer is:
gaped
'yawned' is the definition.
('gape' can be a synonym of 'yawn')
'opening with journalist' is the wordplay.
'opening' becomes 'gap' (gap is a kind of opening**).
'with' means one lot of letters go next to another.
'journalist' becomes 'ed' (short for editor).
'gap'+'ed'='GAPED'
(Other definitions for gaped that I've seen before include "Looked stunned" , "Opened mouth wide" , "shown astonishment" , "Was yawning" , "Stared open-mouthed - yawned" .)