Once headers in Australia’s home win get goalie bamboozled (1,5,3)

I believe the answer is:

a while ago

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'once headers' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'australia's home win get goalie bamboozled' is the wordplay.
'australia' becomes 'A' (abbreviation for Australia).
'home' becomes 'H' (abbreviation as used in sports fixtures).
'win' becomes 'w' (abbreviation in sport).
'get' is an insertion indicator.
'bamboozled' indicates anagramming the letters (I've seen this in other clues).
'a'+'h'='ah'
'ah' enclosing 'w' is 'awh'.
'goalie' anagrammed gives 'ileago'.
'awh'+'ileago'='A WHILE AGO'

'in' acts as a link.

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

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