The luckless Johnson had only just returned from a year out with a major pelvic injury when he ruptured his cruciate knee ligament in training last December.
It condemned the former England Under-21 international to another lengthy period on the sidelines, just as he was trying to force his way back into the first-team picture once more.
As the rest of his team-mates either enjoy their summer break, or prepare for next month's World Cup, Johnson must push himself through a punishing fitness regime.
But, while he accepts he will not be fit for the start of the new season, he is hopeful that by September he will be in a position to show new manager Roberto Mancini what an influence he could be within the Blues camp.
"Everything is going well and we are probably looking at September time," Johnson told City's official website.
"I'm working hard and my knee feels good. It's about building fitness now and not doing anything too quickly.
"I have to put the reins on and hold back because one mistake and you're back to square one or worse.
"I have been back to the surgeon three times for check-ups and he's given the all-clear each time."
Another check-up in a month will hopefully provide Johnson with more good news as he hopes to end his awful run of bad luck, which he insists has made him mentally tougher despite the obvious physical setbacks.
"I don't want anyone feeling sorry for me," he said.
"I was out the year before, so when you find out you're going to have 12 months off again it's gutting, but you have been through it once - you know you can get through it again."