He was never going to start. It's going to be a physical battle the first 60mins which isn't Deulofeu's forte. We had Sterling and Suso start for us in the derby last season and although we drew the game, we lost the physical battle.
Had some chances to decide the match, he is still developing. But for a 19 year old in the Premier League he is doing decent within the minutes he is allowed to play. Making progress!