De la Red fainted 13 minutes into Madrid's Copa del Rey tie at Real Union in October 2008, just three months after helping Spain to Euro 2008 glory.

He regained consciousness on the pitch before being carried off on a stretcher and was later diagnosed with a heart problem.

Spanish football has been rocked in recent seasons by the deaths of both Sevilla wing-back Antonio Puerta and Espanyol captain Dani Jarque due to heart conditions.

De la Red battled to resume his career under new coach Jose Mourinho but has heeded medical advice in opting to call time on his playing days, and now wants to turn his attention to coaching.

"I've fought against this in vain and doctors advised me to stop," he said. "I always dreamt of becoming a football player and to be successful at this club, which is the greatest in the world.

"Real Madrid has watched me grow since I joined the Under-10 side and now it sees me retire from the game.

"I want to become a coach now. I may have a problem in my heart, but it still beats for Madridismo."

He continued: "I am very excited and anxious to start this new stage in my career thanks to the club.

"I will be able to continue to work at a place I regard as my home. I will try to learn the skills of a coach and I will give my all to be successful.

"I would like to eventually coach a great team like Real Madrid, but I really aspire to be satisfied with myself. I want to reach the elite some day."