For Koulibaly, the decision was not a huge surprise and he has nonetheless been impressed by the 47-year-old boss.
“The new coach came with some good ideas, he’s a real coach,” the player told Senegalese outlet Le Quotidien.
“He did some good things with Brighton. Now he is a Chelsea manager. He has guidelines, expectations. It’s up to me to be patient, it’s up to me to show that I deserve to play, to show in training that the coach can trust me.
“Compared to this, there will be no problem. We are also in the first weeks, it is normal for the coach to rely on players who are used to the Chelsea badge and who have been there for a very long time.
“When I will be at 100 per cent, there will be no problem, I will play again God willing.”
Chelsea paid £33million for the veteran centre-back in the summer and Koulibaly, currently on duty with Senegal, did not hesitate in signing on the dotted line.
“We arrived at a moment when I wanted to change my life, question myself and embark on a new challenge,” he explained.
“Chelsea came in and my choice was not long in making. They are one of the five best clubs in the world, with a great record, a team that is used to winning. When they called me, I gave a positive answer directly because it was also good to play in the Premier League.
“I think it was time to discover something else. I am very happy to be there. It was a bit difficult at first, because eight years of my life had to be moved to London. We had to find a school, get into the London way of life. But I got my bearings so I'm very happy.”