Hesitates to stop groom’s summary dismissal (4,4)

I believe the answer is:

bums rush

'summary dismissal' is the definition.
(term for a dismissal or firing)

'hesitates to stop groom's' is the wordplay.
'hesitates' becomes 'ums' (um can mean to hesitate).
'to stop' indicates putting letters inside.
'groom' becomes 'brush' (groom can mean to brush oneself).
'ums' put inside 'brush' is 'BUMS RUSH'.

I've seen this clue in The Times.

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