The Chelsea boss said on Friday: "I prefer not to talk too much now. We need to know better the situation. I think he's a little bit down because he was very excited to come back. How we build him back was perfect because it was step by step. First play 25 minutes, then 30 minutes, 35, 45, 60 minutes.
"It was in a perfect way we tried to build his confidence and full recovery and for him it's difficult to accept. He feel very disappointed, very frustrated. Now we need to be careful in the way we talk and also assess and try to find the resolution for him to be consistent."