Spain marched into the World Cup quarterfinals with a 1-0 victory over Portugal, a tense, tactical contest in Arlington that doubled as the final World Cup appearance of Cristiano Ronaldo’s storied career.

The decisive moment arrived late, just as extra time loomed. Mikel Merino, only recently back on his feet after being fouled, reacted quicker than anyone in a chaotic sequence. While Portugal protested, Spain recycled possession, Ferran Torres threaded a precise through ball into the box, and Merino ghosted into space before drilling a low shot beyond Diogo Costa. In a single movement, Spain’s midfielder settled a derby that had been balanced on a knife edge.

Portugal responded with urgency, pinning Spain back in the closing minutes. Twice they came close to an equaliser, forcing Spain’s back line and goalkeeper Unai Simón into desperate interventions. Yet the European champions held firm, preserving not only their place in the tournament but also a remarkable defensive record.

Simón’s clean sheet was his sixth in succession at the World Cup, extending a tournament-best shutout streak that has now surpassed the mark once held by Italy’s Walter Zenga. Spain have not conceded in World Cup play since a knockout-round draw two tournaments ago, a run that has turned their defence into the foundation of a renewed title challenge.

For Ronaldo, the night was heavy with symbolism. The all-time leading scorer in international football had spoken openly about this being his final World Cup, and he played like a man determined to stretch the journey. He twice tested Simón in the first half, including a powerful effort that drew a spectacular, back-arching save. When the final whistle sounded, the 39-year-old forward stood motionless for a moment, then walked off with eyes glazed, his last World Cup campaign ending in the round of 16.

Spain now await the winner of the clash between Belgium and the United States, with a quarterfinal date at SoFi Stadium looming. For Merino, whose season has been punctuated by injury and time away from his newborn child, the goal was both catharsis and confirmation. For Ronaldo, it was the closing chapter of a World Cup story that helped define an era.