Pop starts to build up reserves, saving thousands (5)

I believe the answer is:

burst

'pop' is the definition.
(I know that pop can be written as burst)

'starts to build up reserves saving thousands' is the wordplay.
'starts to' indicates taking the first letters.
The first letters of 'build up reserves saving thousands' is 'BURST'.

(Other definitions for burst that I've seen before include "Rope to catch cattle" , "Explosion" , "Exploded" , "Explode, erupt" , "Collapse" .)

I've seen this clue in The Times.

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