Desailly believes Mourinho is the perfect choice for Chelsea.
"He has unfinished business at the club," said Desailly who was at Stamford Bridge for four years and won 116 caps for France.
Desailly credits the Special One for creating the winning psyche that transformed the club.
"He brought a winning mentality to Chelsea," said Desailly.
"And he is the right man for this moment. They say that you should never go back in football but that is not always true. I think there was something in his heart telling him to return to Chelsea.
"He had not finished his work at Chelsea when Roman Abramovich decided he should leave."