Expert movement garnering support (9)

I believe the answer is:

promotion

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'support' is the definition.
(thesaurus)

'expert movement' is the wordplay.
'expert' becomes 'pro' (short for professional).
'movement' becomes 'motion' (synonyms).
'pro'+'motion'='PROMOTION'

'garnering' is the link.
This may not be right. It may belong to another bit of the clue.

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(Other definitions for promotion that I've seen before include "Puffing, perhaps" , "movement?" , "Advancement" , "that should result in more money" , "sales campaign" .)

I've seen this clue in The Times.

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