Spain coach Luis de la Fuente said his team had to keep their feet firmly on the ground despite an impressive 3-0 win over Croatia to kick off Euro 2024 in style on Saturday.
La Roja defeated Zlatko Dalic's side in Berlin in their opening match, launching their bid for a record fourth triumph with goals from Alvaro Morata, Fabian Ruiz and Dani Carvajal.
"We have to stay calm, motivated and proud, that's my message," De la Fuente told reporters.
"The players know the country is going to be very excited, we're aware of that and of the euphoria.
"We just have to stay calm and be professional because staying calm is power."
De la Fuente's side overpowered Croatia in the first half and largely kept their opponents at arm's length in a more relaxed second half.
"Of course this give us a boost, and settles us, but in five days we have a big game against Italy," he continued.
"Above all we have to stay calm, our target is still very far away, we have to just keep our feet on the ground."
Barcelona winger Lamine Yamal, 16, became the youngest player ever to play at the Euros and set up Carvajal's goal with a fine cross from the right.
De la Fuente said he was impressed with how a largely young side performed from start to finish.
"We dug in against Croatia who are one of the best teams in the world and we applied ourselves well in defence," continued De la Fuente.
"We performed in the way we needed to at every stage – for such a young team to do that, with many players playing in the Euros for the first time, staying focused for over 90 minutes was impressive."
- 'Different tactical options' -
Spain had less ball possession than Croatia, reflecting a change from his predecessor Luis Enrique's style, with La Roja now more willing to go direct when it suits them.
"We pressed high very well, won the ball back near the opposition box, we also knew... that we have real versatility and different tactical options," said De la Fuente.
"It's because we have players with different attributes. If you have players with the speed of Ferran (Torres), Nico (Williams), Lamine, (Ayoze) Perez, it gives us options. That's the message we send out.
"We're turning this national team into something with many options. Our opponents know we can hurt them with possession or attacks based on positional play, or we can be very quick on the break too."
Madrid defender Carvajal scored in his club side's Champions League final win over Borussia Dortmund earlier in June and stayed razor sharp on his national team's bow in Germany.
"For the moment I'm the top scorer at the Euros because nobody has scored two," joked Carvajal.
However the right-back said his team gave up too many chances in the final stages to Croatia, with Spain stopper Unai Simon saving a Bruno Petkovic penalty.
"It's true that we all trust each other, but we conceded more chances than we should have if we want to go far," he added.