King Felipe VI of Spain is at the Luzhniki Stadium in Moscow to see his national team play World Cup host Russia.
The king heads FIFA's list of VIP guests for the round of 16 game on Sunday, which also includes Russia's Prime Minister Dmitry Medvedev.
President Vladimir Putin has not returned to the stadium where he watched Russia beat Saudi Arabia 5-0 in the opening game on June 14.
Spain's king is a football fan who, as crown prince, attended the 2010 World Cup final in Johannesburg to see La Roja beat the Netherlands 1-0 in extra time.
He had other business four years ago when Spain was eliminated by a 2-0 group-stage loss to Chile at the Maracana stadium in Rio de Janeiro.
The following day in Madrid, Felipe was sworn in as king after the abdication of his father, Juan Carlos.
