Early form of team event (5)
I believe the answer is:
relay
'team event' is the definition.
'relay' can be an answer for 'event' (I've seen this before). I am not certain of the 'team' bit.
'early form' is the wordplay.
'form' indicates anagramming the letters (another form of the letters).
'early' with letters rearranged gives 'RELAY'.
'of' is the link.
Can you help me to learn more?
(Other definitions for relay that I've seen before include "article in bank" , "supplementary store of anything" , "Pass on - put down again" , "Team of workers" , "Broadcast" .)