David De Gea says it will be "tough" to manage without Casemiro after the Brazilian midfielder's red card in the win over Crystal Palace on Saturday.
Manchester United were made to sweat after a red card to star midfielder Casemiro for violent conduct but survived a nerve-wracking finish to beat Crystal Palace 2-1.
Casemiro says playing for Manchester United has given him a new lease of life in his footballing career.
Casemiro scored twice for Manchester United on Saturday as they beat Reading 3-1 in the fourth round of the FA Cup.
Manchester United will be without the suspended Casemiro when they travel to Arsenal for Sunday's highly-anticipated clash with the Premier League leaders.
Man Utd coach Erik ten Hag defended his decision to use Casemiro in the 1-1 draw with Crystal Palace.