Demolish place over hard crossword? (5,4)

I believe the answer is:

throw down

'demolish' is the definition.
(to throw down is to demolish or break)

'place over hard crossword?' is the wordplay.
'place' becomes 'throw' (throwing is a kind of placing).
'over hard crossword?' becomes 'down' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'throw'+'down'='THROW-DOWN'

I've seen this clue in The Guardian.

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