Unpredictable on-the-spot layout -- is it? (7,5-3)

I believe the answer is:

penalty shoot-out

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'it?' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'unpredictable on-the-spot layout' is the wordplay.
'unpredictable' is an anagram indicator.
'on'+'the'+'spot'+'layout'='onthespotlayout'
'onthespotlayout' is an anagram of 'PENALTY SHOOT-OUT'.

'is' is the link.

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I've seen this clue in The Telegraph.

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