Kroos felt left alone after Casemiro's transfer to Manchester United

Toni Kroos who won four Champions League crowns and two league titles playing next to

admitted he was 'surprised' Casemiro swapped Madrid for

as the

international ended a 9-year spell with the

to join the Premier League side.

Kroos told

podcast:

"The decision surprised me to do that. He has made the decision for himself to do something new again.

"He's 30 and knows for sure that he won't need to do that in two or three years. There were more and more reports, it somehow got hotter.

"In the beginning, I would not have expected it at all, I thought it was just a rumor at first. But there are one or two newspapers here that are a bit better informed.

"As more and more people reported and talked about details, I was awake at three or four o'clock at night when I was sick. Then I just wrote to him [asking] if he would really leave me alone."

Casemiro

made his debut for United in their Saturday's 1-0 victory over

, coming in as a substitute. The Red Devils will be back in action on Thursday when they face

in a

match.

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