Horse, in grass, got up again (9)

I believe the answer is:

remounted

'got up again' is the definition.
('mounted' is an answer for 'got up' so perhaps 'remounted' is OK for 'got up again')

'horse in grass' is the wordplay.
'horse' becomes 'mount' (mount is a kind of horse).
'in' indicates putting letters inside.
'grass' becomes 'reed' (type of grass plant).
'mount' inserted within 'reed' is 'REMOUNTED'.

(Another definition for remounted that I've seen is " Got on again".)

I've seen this clue in The Daily Express.

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