Wayne Rooney explains why he is not convinced by Manchester United's decision to sign Casemiro

Former striker Wayne Rooney has questioned Manchester United's decision to sign Real Madrid midfielder Casemiro, insisting that they should have tried to turn to somebody younger.

United announced on Friday evening that they have reached an agreement with the Spanish giants to sign the Brazilian international, subject to him agreeing personal terms, securing a UK visa and passing his medical. The club reached out to Madrid on Wednesday to find out whether or not Casemiro would be open to a move to Old Trafford and the deal soon moved at a rapid rate of knots.

Although it is not officially signed and sealed just yet, the midfielder just has to complete a handful of formalities before he can be unveiled as the club's fourth signing of the summer transfer window. He will end their search for a central-midfielder, although he possesses very different qualities to those of long-term target Frenkie de Jong.

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The 30-year-old is a defensive-minded midfielder who can protect the back-four and do the dirty side of the game, whereas De Jong is a player that likes to get on the ball, dictate proceedings and play through the lines. Casemiro, however, fills a position that United have needed to strengthen for years, meaning his impending arrival has been well received by the supporters.

Rooney, however, has expressed doubts about United's decision to move for the Brazilian, although he admits he will significantly bolster their midfield options. His biggest concern is Casemiro's age, suggesting that the Reds should be looking to sign younger players.

"Casemiro, United's new signing, will not be eligible to face