Nasty sort starts to drink all my port (9)

I believe the answer is:

rotterdam

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'port' is the definition.
(I know that Rotterdam is a port)

'nasty sort starts to drink all my' is the wordplay.
'nasty sort' becomes 'rotter' (I can't justify this - if you can you should believe this answer much more).
'starts to' says to take the initial letters.
The initial letters of 'drink all my' is 'dam'.
'rotter'+'dam'='ROTTERDAM'

Can you help me to learn more?

(Other definitions for rotterdam that I've seen before include "city abroad" , "European city" , "foreign city" , "European port" , "Major North Sea port - tarred tom (anag)" .)

I've seen this clue in The Times.

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