Rackets raised to receive Sabalenka's opening spell (7)

I believe the answer is:
session
'opening spell' is the definition.
The definition and answer can be both related to communication as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'rackets raised to receive sabalenka's' is the wordplay.
'rackets' becomes 'noises' ('noise' can be a synonym of 'racket').
'raised' says the letters should be written backwards (going up in a down clue).
'to receive' indicates putting letters inside.
'sabalenka' becomes 's' (this might be a standard abbreviation I've not previously seen).
'noises' back-to-front is 'sesion'.
'sesion' enclosing 's' is 'SESSION'.
Can you help me to learn more?
(Other definitions for session that I've seen before include "Studio recording period" , "Meeting of a court or parliament" , "Hearing, sitting" , "Official sitting" , "School term" .)
