Flu panic disrupted a sporting event (3,5)
I believe the answer is:
cup final
'a sporting event' is the definition.
(type of sporting event)
'flu panic disrupted' is the wordplay.
'disrupted' indicates an anagram.
'flu'+'panic'='flupanic'
'flupanic' with letters rearranged gives 'CUP-FINAL'.
(Other definitions for cup final that I've seen before include "Deciding match in knock-out competitions" , "Last footballing tie" , "Major football match" , "Concluding game in FA competition" , "Last important game" .)