Cape Town - Former Manchester United and England striker Andy Cole says he faces a long road to recovery following a recent kidney transplant.
The former Premier League star forward was forced to have a transplant in April after suffering kidney failure when he contracted an airborne virus in 2015.
His nephew Alexander was the donor.
Cole, 45, has just returned to his ambassadorial role for United although his physical conditon means he is unable to travel to Barcelona for a Manchester United legends game at the end of the month.
"If I push it, I could go backwards or end up back on medication," he said. "There is also a chance of rejection," Cole told the BBC.
"It is a long road ahead. It is a tough road and different to the battles I have had before.
"It is not like getting a football injury, when you go to the gym and work a bit harder."
Cole has recovered well so far and has lost much of the extra weight he gained during the illness.
Cole will be United's assistant manager at the return legends game against Barcelona at Old Trafford in September, and he said he is keen to play in future matches once he is recovered.
"I still get very tired, but I can do a lot more than I was able to two years ago. If this game is played next year I want to be out there," he said.