Sorry I missed that free motorway to Spain (6,2)

I believe the answer is:

pardon me

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'sorry i missed that free motorway to spain' is the definition.
'pardon me' can be an answer for 'sorry' (I've seen this before). I'm not sure about the remainder of the definition.

'sorry i' is the wordplay.
'sorry' becomes 'pardon' (I've seen this before).
'i' becomes 'me'.
'pardon'+'me'='PARDON ME'

Can you help me to learn more?

(Other definitions for pardon me that I've seen before include "Sorry" , "Polite apology" , "Say that again!" .)

I've seen this clue in the Irish Times and the Irish Times (Crosaire).

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