Supporter's trust slightly disturbed, with second coming first (5)

I believe the answer is:

strut

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'supporter's' is the definition.
(I've seen this before)

'trust slightly disturbed with second coming first' is the wordplay.
'trust' anagrams to 'STRUT'.
However, I'm not clear how this is indicated.

Can you help me to learn more?

(Other definitions for strut that I've seen before include "Reinforcing rod" , "Walk proudly like metal support" , "supporter" , "Prop; prance" , "Walk proudly like peacock" .)

I've seen this clue in The Times.

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