Performances wise, nobody has covered themselves in glory this season under Amorim apart from a select few so anybody being mentioned is not a surprise. However, the name checking of Casemiro in pressers with subtle phrasing like 'he's a player that's won it all, he knows it ain't good enough' or 'even Casemiro has to sit on the bench' is obviously a ploy to either motivate him to step up and/or to leave i.e 'you have to try even harder at your age and with your experience because you start at ground zero like everyone else'. Next season will be even tougher for him to play/start, so Amorim is trying to make him realise why wouldn't he take the same pay check elsewhere and play on his own terms?
Of course if he wants to stay, no one can change that.