Failure to reject what a sucker will fall for? (5,4)

I believe the answer is:

lemon drop

'what a sucker will fall for?' is the definition.
(a lemon drop can be sucked)

'failure to reject' is the wordplay.
'failure' becomes 'lemon' (lemon can mean a failure or useless person).
'to reject' becomes 'drop' (drop can mean to reject or abandon).
'lemon'+'drop'='LEMON-DROP'

(Another definition for lemon drop that I've seen is " Fruit sweet".)

I've seen this clue in The Times.

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