The midfielder, 22, has signed a new deal to 2030.
Turrientes said: "I am very happy and content, it is a very special day for me and those around me. I think I have worked hard throughout my time at Zubieta to be able to reach days like this.
"I have to thank the club for the trust they have had in me and, for my part, continue working day after day and eat the grass every chance I get.
“I joined Real when I was 11, but I have been a fan of Real since I was born, I have the txuriurdin colours inside me. The road has been difficult, with many ups and downs, but I have worked hard to have these special days and I am very happy.”
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