Founder of football body I left (4)
I believe the answer is:
fail
'founder' is the definition.
(thesaurus)
'football body i left' is the wordplay.
'football body' becomes 'fa'.
'left' becomes 'l' (common abbreviation).
'fa'+'i'+'l'='FAIL'
'of' is the link.
(Other definitions for fail that I've seen before include "collapse" , "Be unable to achieve one's object" , "Flunk" , "Fall short" , "Be unsuccessful, say in exam" .)