Laboured breathing in the past new to Pacino (6)

I believe the answer is:

agonal

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'laboured breathing in' is the definition.
Although both the answer and definition are adjectives, I cannot understand how they can define each other.

'past new to pacino' is the wordplay.
'past' becomes 'ago' (similar in meaning).
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'to pacino' becomes 'al' (Al Pacino).
'ago'+'n'+'al'='AGONAL'

'the' acts as a link.

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I've seen this clue in the Sydney Morning Herald.

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