Sees bronco told off on the wagon (5-4,5)

I believe the answer is:

stone-cold sober

'on the wagon' is the definition.
(I've seen this before)

'sees bronco told off' is the wordplay.
'off' indicates anagramming the letters.
'sees'+'bronco'+'told'='seesbroncotold'
'seesbroncotold' anagrammed gives 'STONE-COLD SOBER'.

(Another definition for stone-cold sober that I've seen is " Not a bit drunk".)

I've seen this clue in The Everyman puzzle in The Observer.

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