To us, a record event (6)
I believe the answer is:
discus
'event' is the definition.
(athletics event)
'to us a record' is the wordplay.
I cannot quite understand how this works, but
'us' is present in the answer.
'record' could be 'disc' (eg a CD, compact disc) and 'disc' is found in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for discus that I've seen before include "Athlete's projectile" , "Object thrown by athletes" , "Sporting projectile" , "missile launched" , "Sports projectile" .)