Rex withdraws from foxhunting, possibly result of pricked finger? (5,4)

I believe the answer is:

blood spot

'result of pricked finger?' is the definition.

'rex withdraws from foxhunting possibly' is the wordplay.
'withdraws' suggests deleting specific letters.
'from' becomes 'ex'.
'foxhunting possibly' becomes 'bloodsport'.
'ex'+'bloodsport'='exbloodsport'
'exbloodsport' with 'rex' removed is 'BLOOD SPOT'.

I've seen this clue in The Guardian.

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