Non-U field event records (5)
I believe the answer is:
discs
'records' is the definition.
(I know this)
'non-u field event' is the wordplay.
'non' suggests deleting specific letters.
'field event' becomes 'discus' (discus is a kind of field event).
'discus' with 'u' taken out is 'DISCS'.
(Other definitions for discs that I've seen before include "Records" , "Flat, circular plates" , "Layers of cartilage between vertebrae - they may slip" , "They're round and flat" , "Type of recordings" .)