Chelsea beat Sheffield United 2-0 in the FA Cup quarter finals last night.
However, it was far from a controlled performance and the Blues and Tuchel was not hiding the fact.
“It was a good first half but in the second half, we lost control,” he told BBC Sport. “We were clearly tired after 14 games consecutively, I could feel us tired with a bit of a lack of concentration.
“There were many little faults with a strong opponent in the second half. We were lucky in the second half to keep the clean sheet. I think it is the first time in the 14 matches where we were lucky. It can happen and, in the cup, it is important to go through and this was the target. We reached it.
He added: “Of course, we let them come back because we had full control in the first half. In the second half, we had a big chance with Christian [Pulisic] to finish the game early. After that, we had too many easy mistakes, lost duels and lost concentration and momentum.
“Honestly, I could feel in training in the last days that we were a bit tired with a lack of concentration and things were not too easy. It is normal that it can happen in a game where it is difficult to keep the level up. I was happy to help the guys from the bench with the guys who came in. In the end, we have a win and we will take it.”
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