Mendy returns to the starting line-up today against Manchester City. That will mean a place on the bench for Kepa Arrizabalaga at the end of a week in which he has excelled with a clean sheet at Spurs and a penalty shoot-out save against Aston Villa in the Carabao Cup.
"The situation is clear," said Tuchel. "Mendy at the moment is the number one and the number one is ready to play, not at 99 per cent but at 100 per cent, so he plays.
"It maybe sounds tough but there are no hard feelings. Kepa is a fantastic goalkeeper and we are so happy to have him here. I was so happy that he could show everybody what he shows us here every single day and we are here to push him to the absolute limit.
"The situation can be difficult if we don't talk before but we have so it is clear. He can only play so good because he feels good, otherwise it's not possible to perform like this.
"They push each other, they are happy for each other, they behave like friends in this competition to be number one but the situation is so clear and super calm."
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