The hosts soon increased their lead with two thumping strikes from Marco Asensio, the second of which was given as an own goal to Croatia goalkeeper Lovre Kalinic as it bounced off him after crashing against the crossbar.
Four of the six goals Spain scored in the UEFA Nations League game at Elche came from Real players, who comprised six of the starting 11 of the national team for the first time in 16 years.
Spain versus Croatia had the potential to be an entertaining contest given what the latter achieved at the 2018 World Cup. Spain were in a confident mood after winning their first game under Luis Enrique 2-1 away to England in their Nations League opener on Saturday and once they scored the floodgates opened and Croatia were left chasing shadows.
But, perhaps more importantly, it should also give the players belief in Luis Enrique's methods.
"I've never had the intention to go anywhere", Asensio said, as quoted by FourFourTwo.
Spain global Marco Asensio, who struggled to cement his place in Los Blancos' first team last season, was tipped to leave the 13-time UEFA Champions League winners after Liverpool reportedly showed some interest in him.
"This week everything was flawless".
"They are not from one team or another".
Madrid play Athletic Bilbao at the San Memes this weekend, which, coincidentally, was the same stadium that a fresh-faced 18-year-old Iker Casillas made his debut 19 years ago today.
"Comparisons with the World Cup and tonight do not make sense", Luis Enrique said. "They had an early chance, they didn't take it and then we played brilliantly and scored some great goals". Croatia and England have no points after their respective losses to Spain.
The match also kept Spain's flawless record when playing against Croatia star Luka Modric.
"We can not cry about it, we have to improve", coach Zlatko Dalic said.
"After the first goal we were not so focused, we tried to do things too fast and started to abandon the system".
Vinicius continues to play with Castilla and will likely line out at Alfredo Di Stefano stadium for their Second Division B match against Unionistas de Salamanca on Sunday.