The player also had a message of thanks for La Real and its fans.
"I want to send you this message of goodbye, but also of thanks for what has been an unforgettable year for me," he stated.
"I lived some great moments with this shirt, such as my presentation, my first goal in the Reale Arena, the qualification for the Copa del Rey final and the Europa League and much more.
"You helped me feel like another youth graduate.
"I'll never forget all the support you showed me in the stadium and day to day.
"I want to thank the club for the confidence placed in me.
"I also want to thank my teammates and the club staff for helping me improve each day.
"It's time to say goodbye, but here you have a Txuri Urdin for life."