The Serb is revelling in working with the Portuguese.
"We feel very confident," he said. "We've passed a difficult week for us and everyone can see the big motivation. I hope we're going to start well and finish well. In between we have very hard work, this is our base for the season.
"He [Mourinho] has been in the hearts of all Chelsea supporters in all these years and we are very happy he is here, he can improve us. We've enjoyed the first week but you have to stay focused and we have to prove to him we are good enough to play every game."