Chelsea boss Thomas Tuchel insists he was involved in the signing of Saul Niguez.
The Atletico Madrid loan addition has barely featured since his deadline day arrival.
But the German said: "A club signing? No, we don't do this. Until now we didn't do club signings and coach's signings. We do signings because we decide together because we believe it's a good pick and a good addition to the squad, and this was exactly the case.
"I think every single player needs his time to adapt and Saul needed his time. He competes with a lot of high quality players in midfield.
"We need to understand him a bit better, not in terms of language, but in terms what is his real strength, the detail of the player, what can he add to the squad, where is his maybe unique quality and it was not easy.
"I guess it's the first time he plays for another club than Atletico, he comes from the academy there, and we have to accept the style of the game is so different from Spain to here.
"It teaches us a lesson that everybody needs individual time to adapt and since many days he is stronger, I feel him a bit more relaxed and at the same time that gives him a little bit more freedom to impose his quality. He's very strong in finishing, in arriving in the box.
"In the moment, where we have injured players in the midfield, even Jorgi doubtful for tomorrow, it's the moment for him to be ready and I have the feeling since many days that he is ready and can show what he wants to show."