Compelling fellow circus act (9)

I believe the answer is:

strongman

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'circus act' is the definition.
The definition suggests a singular noun which matches the answer.

'compelling fellow' is the wordplay.
'compelling' becomes 'strong' (I can't explain this - if you can you should believe this answer much more).
'fellow' becomes 'man' (fellow can mean a man).
'strong'+'man'='STRONGMAN'

Can you help me to learn more?

(Other definitions for strongman that I've seen before include "power shower" , "Powerful politician" .)

I've seen this clue in The Daily Express.

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