That was on the back of seven successful seasons in Serie A, but he never quite hit it off, scoring 12 goals in his debut season. Not terrible, but not as spectacular as would have hoped.
He was then loaned to AC Milan, before being brought back to Chelsea by Jose Mourinho in 2005/06, where he scored another 13 goals.
Crespo would then be loaned and sold to Inter where he scored 29 times, but ultimately his time under The Special One left a big impression on him.
Now retired, his final game was for Parma two years ago, he is busy pursuing a career in management, and to do that he is intent on learning from the best.
Crespo paid a visit to Real Madrid this week, to catch up with Mourinho and once again see his coaching methods first hand. And he was glowing about his former boss:
"Working with him is spectacular. He is a winner and a leader who I had a lot of fun with in training. There is something special about him and as a player he makes you feel important.
“I already knew his methods, but I came to get an understanding of how you experience football from the other side of the desk and what it means to be a football coach, from planning to management. Thankfully I have had great coaches in my career and I have learnt from all of them”.
“His trophies speak for themselves. He is a leader and has a lot of charisma. That is not something you can learn; you either have it or you don’t. I will finish my coaching course in June and I want to learn from all the coaches."
Crespo is certainly going about his learning the right way, rather than rushing into management as several ex-players have done.
He has a wealth of experience, playing under top managers throughout his varied career, and who knows - The Argentine could even become Chelsea boss one day?
Do you think Crespo would make a good coach? What do you remember of his time at Chelsea?
image: © jansolo09