The right-back drilled home a crucial strike on Saturday at Villa Park to send Mourinho???s side seven points clear at the top of the Premier League after Manchester City were held to a 1-1 draw at home to Hull.
Ivanovic moved to Stamford Bridge from Lokomotiv Moscow for ??9m in 2008 and after the Serbia international turned in another crucial display, Mourinho believes his signing has proved to be an inspired one.
“He came immediately after I left and after that he made a fantastic contribution for this club. He is a competitive animal with a big heart,??? he said.
“What really matters more is what we as a club feel for him and people like John (Terry) and (Gary) Cahill, guys that without them, you cannot do anything.
???A team is an artist like (Eden) Hazard, it is a defender like Branislav. The mix and combination of talent makes a team.
“Every striker in the world would be proud to score that magnificent goal, it is an amazing goal.
???When he scores that goal and it is three or four nil it is a different feeling. He is a great guy, what he is doing for us is unbelievable.”