Iker Casillas Fernández is a Spanish former professional footballer who played as a goalkeeper and currently works as a football commentator. Popularly dubbed "San Iker" for his ability to produce spectacular saves, Casillas is widely considered to be one of the greatest goalkeepers of all time. He is known for his athleticism, quick reactions and outstanding shot-stopping ability. Having spent the majority of his career at Real Madrid, Casillas is one of the few players to achieve over 1,000 professional career matches, and also holds the record for the most clean sheets for the Spain national team. Currently, he works for RTVE, Movistar Plus+ and Azteca Deportes.

The goalkeeper is a position in association football. It is the most specialised position in the sport. The goalkeeper's main role is to stop the opposing team from scoring. This is accomplished by having the goalkeeper move into the trajectory of the ball to either catch it or direct it further from the vicinity of the goal line. Within the penalty area goalkeepers are allowed to use their hands, giving them the sole rights on the field to handle the ball. The goalkeeper is indicated by wearing a different coloured kit from their teammates and opposition.