"We tried everything throughout the week and yesterday in training but it was so-so," Thomas Tuchel said about Edouard Mendy's injury, as quoted by the official Chelsea website.
"It comes from the last-minute kick against Zenit in the Champions League so it’s very painful and he felt it.
"He was not 100 per cent comfortable to go for a full stretch or to land on it so we decided to go for 100 per cent, which was Kepa, and have Edou with us to be supportive and to have a good energy.
"I’m so happy that Kepa played a crucial role today to have a clean sheet because it’s what he deserved.
On Pulisic, the boss added: "I think for Christian the game against Aston Villa [in the Carabao Cup in midweek] is maybe a bit too close. I hope that I’m wrong but this is my impression.
"He’s not in training so far but let’s see tomorrow. Maybe if he had a good progression today, maybe it’s possible. It would be super nice for us to have him but for me it’s a bit doubtful."
Chelsea are taking on Villa on Wednesday, and it might've been the game to involve players who do not feature that often, including Pulisic.
Mendy would have probably missed that game anyway, so he'll be focused on his recovery for the all-important clash against Man City on Saturday.
