'Expressionless, unexciting' -- review unfavourably (7)

I believe the answer is:

deadpan

'expressionless' is the definition.
(I know that expressionless can be written as deadpan)

'unexciting review unfavourably' is the wordplay.
'unexciting' becomes 'dead' (dead can mean dead boring).
'review unfavourably' becomes 'pan' (pan can mean to review badly).
'dead'+'pan'='DEADPAN'

(Other definitions for deadpan that I've seen before include "Blank" , "with emotionless face" , "Keeping a straight face" , "Dry" , "Impassive" .)

I've seen this clue in The Telegraph.

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