Pizarro opponent (5)
I believe the answer is:
incan
'pizarro opponent' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for incan that I've seen before include "Pachacuti for example" , "Of an Andean civilisation overthrown by Pizarro in 1533" , "Relating to ancient South Americans" , "Member of old Andean civilisation" , "Like some South Americans" .)