Di Matteo has no concerns about Terry's mental or physical wellbeing.
"As a human being there are certain aspects of life that will faze you," he said.
"But, if you look at his career, he's always got on with it. He's a confident player. I played with some great players in my career. There were certain players who were very, very confident.'
Indeed, former Italy star Di Matteo compared Terry's mental strength with that of some of the best players he had ever played with - "Paolo Maldini, [Angelo] Peruzzi, [Pierluigi] Casiraghi, [Alessandro] Costacurta, [Alessandro] Del Piero, all players who have spent 15 to 20 years at the highest level, domestic and international football."
He added: "To be able to survive for so many years at the top level in football, at club and international level, you need to be mentally strong.
"That goes for all the players who have had that kind of career, not just JT."