Capital once managed by board (7)
I believe the answer is:
rangoon
'capital once' is the definition.
(I've seen this before)
'managed by board' is the wordplay.
'managed' becomes 'ran' (I've seen this before).
'by board' becomes 'goon' (I am not sure about this - if you are sure you should believe this answer much more).
'ran'+'goon'='RANGOON'
Can you help me to learn more?
(Other definitions for rangoon that I've seen before include "Former capital of Burma" , "Asian capital" , "It's now Yangon in Myanmar" , "Former name of the capital of Myanmar" , "Former Burmese capital" .)