Defeat leading group (5)

I believe the answer is:

upset

'defeat' is the definition.
(I know that upset is a more specific form of defeat)

'leading group' is the wordplay.
'leading' becomes 'up' (up can mean winning a sports match).
'group' becomes 'set' (both can mean a collection).
'up'+'set'='UPSET'

(Other definitions for upset that I've seen before include "Disturb, physically or emotionally" , "Discomfit" , "Overturn - perturbed - disordered" , "Caused grief" , "Disrupted; knock over" .)

I've seen this clue in The Times.

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