The Black Cats have spent much of the summer chasing the 19-year-old's signature, but have so far been unable to get a deal over the line.
Reports suggest that an agreement is now almost done, with the highly-rated winger set to become the latest new arrival in a busy summer at the Stadium of Light.
Di Canio is, however, reluctant to be drawn into a transfer debate before all of the relevant paperwork is completed.
He is convinced that Mavrias would be a shrewd acquisition if he can be brought on board, but has been in the game long enough to know that you cannot take anything for granted in professional football.
Di Canio said in the Sunderland Echo: "Until a player signs, I would prefer not to say too much about them.
"But what do I know about Mavrias? I know him, I know that he is a very good prospect, I know that he's a very exciting player.
"But I don't want to talk about him, or any more about what was said about (Stephane) Sessegnon at the weekend because things you say about transfers can easily cause problems and confusion, so I would prefer to wait and see."