Patriot song composed for champion (11)
I believe the answer is:
protagonist
'for champion' is the definition.
(synonyms)
'patriot song composed' is the wordplay.
'composed' is an anagram indicator.
'patriot'+'song'='patriotsong'
'patriotsong' with letters rearranged gives 'PROTAGONIST'.
(Other definitions for protagonist that I've seen before include "Hero" , "Chief character in a story" , "Advocate" , "Leading player" , "Lead character" .)