Immediately after his extra-time goal in Spain's 1-0 win over the Netherlands last year, Iniesta removed his jersey to show a white cutoff shirt bearing the words: "Dani Jarque siempre con nosotros" (Dani Jarque always with us).
Jarque, Espanyol's captain, collapsed and died aged 26 on a preseason tour of Italy in August 2009.
Iniesta, who plays for Espanyol's city rival Barcelona, was praised throughout Spain for putting aside club rivalry to make the gesture.
Visitors can see the vest on matchdays and tours at Cornella-El Prat arena.
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