Whatever the Plaza de Colón in central Madrid lacks in elegance or romance, it more than makes up for in patriotic fervour and outsized vexillological allure.

By 8pm local time on Sunday, the square was filling with thousands of spectators who were congregating around a giant screen to cheer on Spain as and clinched a fourth Euro title.

Overhead, opposite the statue of Christopher Columbus, for whom the square is named, flew the largest flag in Spain – an epic banner that measures 21m by 14m and weighs 35kg, which is roughly the same as a decent-sized adult Alsatian.

Still, the crowd had brought a few more flags of their own, just to be on the safe side, and the capital’s metro system brimmed with people in Spain strips and rojigualdas tied at the neck and worn as cloaks.

Spain’s appetite for victory had been well whetted by a few hours earlier.

“I’ve already done my job,” Alcaraz said after his win. “Now let’s see to the football. It’s going to be a really difficult match.”

Madrid’s mayor, José Luis Martínez-Almeida, concurred: “An epic start to the afternoon from Spain. Now to finish it off!”

SW19 honour defended, all eyes shifted from the 21-year-old Alcaraz to the 17-year-old Lamine Yamal, the breakout star of , and to his teammates.

“Tonight is a matter of pride for Spain,” said Javier Adsuar, a 21-year-old from Elche.

“Alcaraz did brilliantly winning the tennis but football is much more important – and I think Lamine Yamal and Nico Williams will score for us tonight.”

Adsuar also felt it was time to give the Spain manager, Luis de la Fuente, a little very belated credit. He had, after all, come a long way from the stinging and ignominious defeat to Scotland in last year’s qualifiers.

“At the beginning of the tournament I wasn’t sure about De le Fuente, but now he’s a god to me.”

His friend, Gabriel Paco, was in little doubt as to the game’s outcome. “Spain is going to win because we’re really good and we’re a better team than England.”

Violeta Macía, who was in Madrid from Alicante province with her friend Maria José Rodríguez and María José’s 10-year-old daughter, Adriana, was a little more cautious in her predictions.

“I think Spain is going to win but it’s going to be tricky as a lot of expectations have been created and football can be a tricky business.”

Adriana, a keen footballer, was more prepared to stick her neck out. What would the final score be? “2-1 to Spain,” she replied, without missing a beat.

For some, Spain’s showdown with England carried an additional weight and importance. As , the young, hungry and diverse team had succeeded where so much else had failed by managing to unite a divided and fractious nation.

“At a time in Spanish political and social life when polarisation and fragmentation seem to monopolise private and public conversations, the success of the Spanish football team … has become a celebrated meeting point for millions of citizens,” the paper noted.

As kick-off approached, the bass-thumping sound system in the square cranked up the volume and Viva España poured from the speakers, prompting a remarkably tuneful sing along from the crowds whose busy flags dispersed pink smoke across the plaza.

Rubén Rodríguez, a 22-year-old from the capital, was already buoyed up by Alcaraz’s victory, which could only have been a good omen. As he waited for his friends and their booze supplies to turn up, he offered his optimistic take on Sunday’s prospects.

“I think it’s going to be a tough game because it’s always hard to play a team that scores last-minute goals,” he said. “But I think we’ll still get the winning goal we need. And anyway, fuck it, Carlos Alcaraz is the greatest tennis player in the world – and maybe one of the greatest in history. Maybe we can do the double. Maybe today’s the day.”

And so it turned out to be. Young Adriana’s prediction was dead on and, as the final whistle blew, the crowd roared while, above them, the Alsatian-heavy flag of the new European champions fluttered in the evening breeze.