A moment of sheer tactical brilliance in the dying moments of the match saw Spain break Portuguese hearts and book their place in the quarterfinals of the World Cup. Substitute Mikel Merino’s stoppage time strike secured a hard-fought 1-0 win over Iberian rivals Portugal at the AT&T Stadium on Monday, drawing the curtain on Cristiano Ronaldo’s legendary World Cup career.In a tense encounter that seemed destined for extra time, the most important moment came in the 91st minute. In the recent tie, Arsenal midfielder Merino has shown an elite presence of mind. While the Portuguese defense stood static, debating the referee’s whistle, Merino quickly restarted the game. He threaded the ball, raced into the box, and calmly slotted a clinical return pass from Ferran Torres past a helpless Diogo Costa.It was a masterstroke from Luis de la Fuente, who introduced Merino in the 85th minute. The midfielder, who endured an injury-plagued season but still helped Arsenal win their first Premier League title in more than two decades, proved to be Spain’s oldest wildcard.The victory marked a historic milestone for La Roja, who marched into the quarterfinals for the first time since their triumphant 2010 campaign in South Africa. Victory was anchored by an impregnable defense; Goalkeeper Unai Simón extended his historic World Cup record to 609 minutes without conceding, anchoring Spain as the first team to record six consecutive clean sheets in the history of the tournament.For Portugal and the 41-year-old Ronaldo, it was a bitter, tearful farewell. The international icon, who bowed out with a staggering 146 goals and 233 appearances, was hungry for service all night in a disciplined Spanish backline.Eight years after Ronaldo’s iconic hat-trick lit up a thrilling 3-3 draw between these sides in Russia, this 105-year-old rivalry has been settled by defensive grit and quick thinking. Spain will now travel to Inglewood, California, to face the USA or Belgium on Saturday.