Lopez left Real this week for Milan.
The letter on Real's website read: "Thirty-two years ago, I was born in a small village in the province of Lugo, Paradela. I dreamed about being a footballer, but I never imagined that I would one day play for the club of my heart, Real Madrid. It is something that I will always be proud of.
"For an academy player to return to the club of their life is the greatest thing.
"I leave happy, because I have given my all. My only objective was to work day upon day with respect, dedication and to passionately defend the values of the best club in the world.
"For all of this I can say with great pride that every minute I spent with Real Madrid was like a gift sent from the heavens."
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