Sustain pair with tea but no starter (7)

I believe the answer is:

prolong

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'sustain' is the definition.
(synonyms)

'pair with tea but no starter' is the wordplay.
'pair with' becomes 'pr' (abbreviation. I am not sure about the 'with' bit.).
'tea' becomes 'oolong' (oolong is a kind of tea).
'but no starter' means to remove the first letter.
'oolong' with its initial letter taken away is 'olong'.
'pr'+'olong'='PROLONG'

Can you help me to learn more?

(Other definitions for prolong that I've seen before include "String out" , "Perpetuate" , "Stretch out" , "Make last" , "Draw out" .)

I've seen this clue in The Independent.

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