Back-to-back golds by previously unknown Spanish hero (5)

I believe the answer is:

zorro

'spanish hero' is the definition.
(Spanish vigilante hero)

I cannot understand how the rest of the clue works.

(Other definitions for zorro that I've seen before include "'The Mark of - - ' (film)" , "Hispanic Robin Hood" , "Masked hero" , "Swashbuckler; fox" , "Swashbuckling hero" .)

I've seen this clue in The Times.

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