Assembled the pots as speedily as possible (9)

I believe the answer is:

posthaste

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'speedily as possible' is the definition.
The definition suggests a singular noun which matches the answer.

'assembled the pots as' is the wordplay.
'assembled' is an anagram indicator.
'the'+'pots'+'as'='thepotsas'
'thepotsas' is an anagram of 'POSTHASTE'.

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(Other definitions for posthaste that I've seen before include "Express" , "as fast as possible" , "Like Bat out of Hell" , "Speedily" , "As quickly as possible" .)

I've seen this clue in The Globe and Mail.

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