The former Spain captain is now 37 but remains a key part of the Porto side, having played in every game so far this season as his team sit atop of both the Primeira Liga and their Champions League group.
“[If the national team called,] I would be delighted,” Casillas told Jorge Valdano in an interview with Movistar.
“Of course [I would return to Real Madrid], I can’t forget where I grew up.”
Speaking about his acrimonious exit from the Santiago Bernabeu and subsequent move to Porto in 2015, Casillas appeared at ease with his decision and believes it was the correct move.
“This has been a step in the right direction,” he said in relation to his Portuguese adventure. “If I had continued at Real Madrid, I would have had a worse ending than I did.”
The remainder of the interview will be aired in full on November 21.
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