Luka Modric frustrated after a still in strong position, while the Spaniards partying wrapped for the kick-off.
With six players who also came into action in the lost world cup final with France (4-2), were the Croats total no match against the unleashed Spain.
Saul Niguez, Marco Asensio, Rodrigo, Sergio Ramos and Isco were in the Estadio Martinez Valero. Lovre Kalinic made on behalf of Croatia is an own goal.
Spain is after two duels are undefeated in the Nationas League. Earlier this week, with a 2-1 won England.
For Croatia was the duel with the world champion of 2010 in the first match in pool 4 of Division A of the new competition. Five days ago, played the team of national coach Zlatko Dalić in a friendly duel with 1-1 gelijkgespeeld against Portugal.