Deputy anaesthetist to inject whiskey (6,3)

I believe the answer is:

number two

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'deputy' is the definition.
(I've seen this before)

'anaesthetist to inject whiskey' is the wordplay.
'anaesthetist' becomes 'number' (I can't explain this - if you can you should believe this answer much more).
'inject' is an insertion indicator.
'whiskey' becomes 'W' (phonetic alphabet: alpha, bravo, charlie etc.).
'to' placed around 'w' is 'two'.
'number'+'two'='NUMBER TWO'

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(Other definitions for number two that I've seen before include "deputy" , "Dump" , "Assistant" , "vice" , "Second in command" .)

I've seen this clue in The Independent.

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