The Brazilian midfielder was dismissed during the Red Devils' goalless draw at Southampton for a high challenge on Carlos Alcaraz, this coming after being red carded during Man United's win over Crystal Palace last month.
Advertisement
The red card, which sees Casemiro miss Man United's next four domestic outings, was brandished by referee Anthony Taylor after VAR official Andre Marriner advised him to look at the incident again.
A lack of consistency is something that's particularly irked Ten Hag, who made reference to Leicester defender Ricardo Pereira escaping a red card for a stamp on Chelsea's Joao Felix on Saturday - a match Marriner officiated.
Advertisement
Ten Hag also spoke about how Casemiro never received a straight red throughout his nine-year spell at Real Madrid, which saw him make over 330 appearances.
"What I think is the inconsistency, players don't know anymore what is the policy," Ten Hag said.
"And I think it's all across. We see it with Premier League yesterday: Leicester-Chelsea, the VAR is not coming on the line. Today, it's coming on the line. And then it's two penalty situations, but they don't come on the line. Especially the first one, it was clear and obvious handball so what is the policy?"
When asked if he had asked Taylor for clarification on the policy, Ten Hag replied: "Of course, we talk but not a lot, so some questions we have.
Advertisement
Advertisement
"There's another one: inconsistent. The referee is coming in the start of the season with a policy. We are Premier League, it's coming strong here, we want intensity.
"Casemiro is across European games, over 500 games he never had a [straight] red card. Now he has two. Think about that. He plays tough but he plays fair. And also in this, he's playing fair, same as against Crystal Palace, so it's very debatable.
Advertisement
"Everyone who knows something about football, you know, and of course, when you freeze it, it looks bad. But everyone who knows something about football, who was acting on top football, they know what is bad, what isn't bad and what is fair. And I tell you: Casemiro is a really fair player. Tough, but fair."
The comments by the Dutchman haven't gone down well with talkSPORT's Adebayo Akinfenwa, who labelled them as 'irrelevant'.
Asked if Casemiro needs to adapt his game in England, Akinfenwa said on The Boot Room: "Of course. What do you want to do, change the rules and the playing styles just because one player played in another country?
Advertisement
"For me that is such an irrelevant statement [from Ten Hag]. You can argue the Premier League is the best league in the world. He's come into this so therefore it's differs. Different officials, different tackles, it's different.
"The tackles are red card offences… it's an irrelevant statement."