The Ivory Coast international has revealed he knew Chelsea were watching when we was establishing himself at Reims.
He recalled to the Guardian: "When I heard about Chelsea's interest, it was actually when I was in Reims, before joining Rennes. It was of course pretty amazing to hear that, especially in my case, three years before I was without a club.
"When you hear about something like that, you have to leave it to one side because it can be distracting. But it worked for the best, I played my season in France and it went really well and when the offer was officially made I did everything I could to join Chelsea because it's a club that I have loved for years.
"It's a real source of pride for me. I wouldn't say it's the end and the ultimate goal, but it's true that it's a real step in the right direction for me as a player. I am someone with a lot of ambitions and a lot of goals, but I prefer to keep them to myself. These are the things that motivate me to do my best every day.
"I'm someone who likes to take things step by step, I don't like to jump in front of myself, I like to take things to the next level before I continue. I work every day to do the best for my team, so I have a lot of ambitions like anyone when they join a team as big as Chelsea."