He announced today: "Chelsea means a lot to me. I came here with the intention of only staying for a year and it ended up being four years. Not just for me but for my family, too.
"My sons play for Chelsea so it's a source of great pride to be a part of the Chelsea family literally because my sons are here. I hope they can continue their careers here at this victorious club that many players wish to be part of.
"I think in everything I did here over the four years, I always gave my all. But, unfortunately, everything has a start, a middle and an end. That doesn't mean that this is a definitive end. I hope to leave the door open so that in the near future I can return, albeit in another role here.
"Butit's an indescribable love. I can only say thank you.
"It is already hard saying goodbye in the most normal of circumstances but when there is a mutual love, it's even harder. But one a Blue, always a Blue.
"(It's been a) dream, definitely a dream. Not even in my wildest dreams did I imagine that I could achieve such great things and win one of the best professional titles, the Champions League, at one of the biggest clubs in the world.
"Goodbyes are for those that leave and don't come back. I intend on coming back one day..."