Thomas Tuchel struggles to understand why his Chelsea side were unable to overcome Juventus on Wednesday night.
Chelsea's unbeaten start to the season came to an end on Saturday when they fell to a 1-0 defeat to Manchester City before losing in Turin in their second Champions League group game.
Following the 1-0 defeat to Juve, with Chelsea registering just one shot on target, the German has labelled the defeat "strange" and says his players "were a bit slow and tired".
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"I think we started not sharp enough," he said.
"We struggled to create our own rhythm and intensity because they were so deep and passive. We were lacking runs.
"We were so good in training yesterday and not good enough, not free enough, today. I don't know why.
"I felt we were a bit slow and tired, mentally slow, decision-making. That's why it's a strange one to analyse. We had a day off and two very good training sessions yesterday.
"We were absolutely sharp, looked very fresh and very hungry, and ready for a bounce back.
"It's very difficult to put on a high rhythm against a team who defends so deep. If we defended deep against City it was difficult for them to create chances.
"It was the same for us here. But the difference was we gave two big chances and gave the belief back into the stadium."
Romelu Lukaku was lacking service throughout the game just like he was against City. Tuchel repeated his side were "lacking runners" against defence-minded Juve.
"Manchester City scored from a set-piece with a deflected shot against us. Sometimes you need this. If a team defends deep, it's hard to find your own rhythm," he said.
"We were lacking runners. Once we started to do other things, we made mistakes and that cost us a bit of belief. A shooting problem. If we don't shoot, they cannot be on target. If you play against a deep block like today, it's hard to take shots.
"We found the spaces, it wasn't easy. We had a lot of shots, but I think there are some chances late in the game where it wouldn't have been so hard to find the target."
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