Mikel Merino delivered a late blow to Portugal as Spain secured a dramatic 1-0 victory in their FIFA World Cup 2026 Round of 16 clash, ending Cristiano Ronaldo's hopes of a memorable farewell tournament.

After a tightly contested battle with few clear chances, Spain found the breakthrough in stoppage time. A quick free-kick move involving Fabián Ruiz and Ferran Torres opened up the Portugal defence, allowing Merino to race through and calmly slot the ball past Diogo Costa.

Portugal pushed for an equaliser but could not find a response, as Spain held on to book their place in the quarterfinals and extend their unbeaten run. For Ronaldo, the defeat marked another heartbreaking World Cup exit as his final campaign on football's biggest stage came to an end.

Roberto Martínez's side struggled to create clear-cut opportunities, with Nuno Mendes seeing a deflected effort crash off the crossbar in the first half and Bernardo Silva missing a late chance to force an equaliser.

Spain were not at their fluent best either, but could have made the result more comfortable had Mikel Oyarzabal taken an early opportunity with greater composure. In the end, Mikel Merino's late strike was enough to send La Roja through to the next round.

Spain advanced to the quarterfinals for the first time since winning its only World Cup title in 2010 in South Africa. Spain will play either the United States or Belgium on Friday in Los Angeles.

Spain started brightly and should have taken the lead inside the opening 10 minutes when Dani Olmo sent Mikel Oyarzabal through on goal, but the forward dragged his effort wide with only Diogo Costa to beat.

Ronaldo came close to breaking the deadlock himself, forcing Unai Simón into a save from a tight angle as he looked to add to his three goals in North America.

Luis de la Fuente's side continued to apply pressure, with Lamine Yamal and Álex Baena both testing Costa in quick succession, including a superb fingertip save from the Portugal goalkeeper.

Ronaldo, who received a mixed reception from the crowd, struggled to make a major impact in his central attacking role as Portugal looked to find a way through. However, Roberto Martínez's team finished the first half strongly and came closest to scoring when Nuno Mendes' effort took a deflection off Pedro Porro's head and crashed against the crossbar.

Yamal endured a difficult battle against Mendes, who was eventually forced off with an injury after 56 minutes, dealing another blow to Portugal.

With the match lacking a decisive moment, Ronaldo showed his frustration after a misplaced pass, while Martínez introduced fresh legs with substitutions in the 71st and 83rd minutes but kept his captain on the pitch.

Just when the game appeared destined for extra time, Arsenal midfielder Mikel Merino produced the decisive moment, calmly finishing late on to send Spain through after a tightly contested encounter.