The tale involved sportsperson (7)
I believe the answer is:
athlete
'sportsperson' is the definition.
(I've seen this before)
'the tale involved' is the wordplay.
'involved' indicates an anagram (involved can mean confusing or complex).
'the'+'tale'='thetale'
'thetale' with letters rearranged gives 'ATHLETE'.
(Other definitions for athlete that I've seen before include "Announces impending danger" , "The late one is very fit, oddly" , "front-runner, possibly" , "One competes in sports" , "expected to be agile, of course" .)