Stroke pet on top of paw and go off (3,6)

I believe the answer is:

dog paddle

'stroke' is the definition.
(dog paddle is a kind of stroke)

'pet on top of paw and go off' is the wordplay.
'pet' becomes 'dog'.
'on top of' indicates taking the first letters.
'and' is a charade indicator (letters next to each other).
'go off' becomes 'addle' (eg an egg might addle).
The first letter of 'paw' is 'p'.
'dog'+'p'+'addle'='DOG PADDLE'

(Another definition for dog paddle that I've seen is " Simple swimming stroke of canine origin".)

I've seen this clue in The Guardian.

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