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Asked about his No.9 on Friday, the German manager had nothing but kind words.
“I don't think it's possible that somebody could get more credit, compliments, praise, than Roberto gets from us!" he said. "But it's well deserved.
“He's a fantastic football player. You see him in training and think 'what a work ethic! What an attitude!" and he brings that on the pitch as well. He never rests! You have to tell him 'come on, stop, sit here, calm!
“I hear in the stadium that obviously people like him – good idea! But I have no real idea if anybody else thinks he's important or whatever. He is important to us, as all of the other players are.
"I'm pretty sure if I gave the players the opportunity to have a free choice to build their own teams in training then he would be one of the first picks! That's maybe the best way I can put it, the best thing I can say about a footballer.”
Video and analysis by Nouman.