Member of the side (3)

I believe the answer is:

leg

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'member' is the definition.
(leg is a kind of member)

I cannot understand how the rest of the clue works.

(Other definitions for leg that I've seen before include "Stage (of race)" , "Projecting support for chair or table" , "prop" , "Gigot" , "Run < on" .)

I've seen this clue in the Evening Standard.

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