The 32-year-old centre-half has been in the spotlight for a number of controversies both on and off the pitch in recent seasons but has already made 10 appearances in all competitions this term.
And although Mourinho admits he questioned the direction of Terry’s career before the Portuguese coach’s return to west London, he feels the defender is now on his way back to his best.
“He’s recovering his self-esteem,” Mourinho told the Guardian.
“In the last few years he was not playing a lot, he had problems on the pitch, he had problems outside the pitch, he had suspensions for different reasons, he had injuries, he had managers who didn’t trust him enough. And it looked like, at a certain moment, his career was going in the wrong direction.
“Even I was questioning, from far away, what was happening to this guy: physical problems, psychological problems, what is going on?
“I’m happy he’s proving he’s still a top player. He plays in a position where age doesn’t make a huge difference. It’s a position where players rely more on positioning, on reading the game, and being in the right place at the right time.”
Mourinho continued: “You go to many clubs and top clubs and central defenders are 30 to 34. John is proving his quality. With what he did at Chelsea in the last decade, I think he deserves to be back on track.”