Johnson, who left Stamford Bridge for Portsmouth in summer 2007 - shortly before the end of Mourinho's first reign - before moving on to Anfield two years later, claims he lost faith in the Portuguese after being dropped ahead of a big Champions League game against Barcelona.
"It was difficult for me under Jose at Chelsea because there was a moment when he said I deserved to play on merit," the 29-year-old told the Daily Mail. "He said if I played well in the next game I would play the week after. I got man of the match so he couldn't drop me.
"Then in the next game he said the same thing and I got man of the match again. Then we had another game and after that Barcelona. I remember speaking to my agent and saying, 'He won't play me in this game because if I play well then he has to play me against Barcelona', and I knew that wasn't going to happen.
"He didn't play me in that game and from that moment I just lost it and thought, 'Well, how am I meant to respect you now? It's just finished'."
"Brendan wouldn't do that. He's shown that if you're good enough you're old enough and you'll play in the big games if you deserve to. So, in terms of man-management, Brendan is definitely better."