Captain of his country and a hero to millions of Madridistas, Casillas also has a strong claim to the title of the finest goalkeeper of his generation. The Real Madrid icon has won tournaments with Spain at Under-15, U-17 and U-19 level, but his crowning glory was lifting the Euro 2008 and World Cup trophies in two stellar years.
Nicknamed San Iker ('Saint Iker') at Real Madrid, Casillas is a rare homegrown talent among a sea of galacticos having joined the club at the age of nine. He made his first-team debut under the current national coach, Vicente del Bosque, in the 1998-99 season and cemented his place the following year when becoming the youngest goalkeeper to appear in a Champions League final when beating Valencia just four days after his 19th birthday. A rare slump in form saw him dropped for the encounter with Bayer Leverkusen two years later but he appeared as a substitute in the second half in Glasgow and won the trophy for Real with a series of superb saves.
Casillas has been an established and respected member of the first XI ever since and has played a major role in Real's extensive success over the past decade - winning almost everything there is to win in the game.
He is Spain's most capped player, breaking the record held by the legendary Andoni Zubizarreta, and it will take some effort from his rivals for his position - the likes of Victor Valdes and Pepe Reina - to wrestle the national jersey off Casillas.
Strengths: As the last line of defence in a team that often pays scant regard to such an art, Casillas gets plenty of practice and frequently demonstrates his impressive reflexes, superb agility and innate ability to pull off a spectacular save. His forceful personality and will to win ensure he is a born leader.
Weaknesses: His aura of invincibility has been slightly dented due to a handful of mistakes and he can be slightly rash when rushing off his line.
Career high: Lifting the World Cup trophy at Soccer City in 2010.
Career low: A humbling experience at the Bernabeu when arch rivals Barcelona smashed six past Casillas in a game that effectively clinched the league title for the Catalans.
Style: Energetic, extravagant, commanding, a leader from the back.
Quotes: "Iker is the perfect captain. I'd give him ten out of ten for everything he does as a keeper, a captain and in the way he behaves. He sees everything so clearly. The whole squad deserve a ten but Casillas more than anyone. As the captain he's the one I speak to the most. He's a phenomenon." Luis Aragones, June 2008.
Trivia: Casillas is very superstitious and every time Real Madrid score a goal he has to touch his own crossbar.