Managed US pop goddess, old hand in Mexico (8)
I believe the answer is:
ranchero
'managed us pop goddess old' is the definition.
I can't judge whether this defines the answer.
'hand in mexico' is the wordplay.
'hand' becomes 'ranch hand' (ranch hand is a kind of hand).
'in mexico' becomes 'ero' (I can't explain this - if you can you should believe this answer much more).
'ranch'+'ero'='RANCHERO'
Can you help me to learn more?
(Other definitions for ranchero that I've seen before include "Mexican cowhand" , "A farm manager" , "See stock farmer" , "Farmworker" , "Mexican farmer" .)
