The former Leicester City midfielder joined up with old boss Enzo Maresca, who he played under last term in the Championship.
But he has not been able to get into the team, as his Premier League appearances have been severely restricted.
“If I score against them I won't celebrate,” he stated back in July of playing against Leicester, which he may do at the weekend in the Premier League.
“I wish them the best of luck for this season. I wanted to test myself at the next level. This felt like the right time and I wouldn't have left Leicester for a sideways move – it had to be a top move.
“I always knew Chelsea were admirers. When Enzo left Leicester, we were on fantastic terms. I wished him the best of luck and he did the same to me. I never in my head thought: ‘He's going to take me when he goes to a big club.’ I don't think I can be that arrogant.
“But when it came about, I was very happy because it meant I could work under him again and continue to evolve. It was perfect for me. I'm a completely different player now coming back into the Premier League than when I was playing in it before. I've evolved, as a player and as a person. I've had the experiences of winning, of dominating games, and understanding football on a different level to what I did before.
“If I made those leaps and bounds in the first year (under Maresca) then I feel excited to see what can happen in the years to come. In football, you can't stagnate, you can't stop learning.”
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