Notices a flailing paddler (8)

I believe the answer is:

canoeist

'paddler' is the definition.
(synonyms)

'notices a flailing' is the wordplay.
'flailing' indicates an anagram.
'notices'+'a'='noticesa'
'noticesa' anagrammed gives 'CANOEIST'.

(Other definitions for canoeist that I've seen before include "Person who paddles a kayak or suchlike" , "rower" , "One using light boat" , "Paddler" , "sportsman" .)

I've seen this clue in The Times.

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