Speaking on Sky Sports, Jamie Redknapp said: "At Manchester United, I see multiple Champions League winners walking around the pitch sometimes like they don't care, and you can't have that.
"I've watched Casemiro for years and he's one of my favourite defensive midfield players in football, I've loved watching him play. But right now, it looks like he's in Soccer Aid.
"Against Bournemouth he played at such a pace where it's a bit of fun and there's celebrities coming on. This is the Premier League! Casemiro is not setting the right examples to the young players. It isn't good enough."
Casemiro, who was key to Man United's top-four success last season, has looked like a different player over the course of the 2023/24 campaign.
Erik ten Hag continues to have faith in the Brazilian but the Bournemouth game last week was a major warning sign about the 32-year-old.
