Mourinho sealed a much-anticipated return to west London in the summer, signing a four-year deal with the Blues just days after quitting Real Madrid.
Ivanovic says he is greatly enjoying working under the 50-year-old but is determined to help Chelsea improve after the international break.
“It’s a big pleasure to play under José,” Ivanovic told Chelsea’s website.
“It’s always a great motivation from his side. We have to push ourselves to improve and we have to motivate ourselves for every single game because he expects that of us, and the club expects that of us.
“It’s a big pleasure but there’s still a lot of hard work to do. We’ve played some good games; we’ve had some defeats, too.
“The team and our performances can improve, we can do better and I think we’ll do it after this international break.”
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