
Just days after scoring a dramatic stoppage-time winner against Portugal, Merino once again made an immediate impact from the bench. Introduced in the 86th minute, he scored two minutes later after Belgium substitute goalkeeper Senne Lammens failed to hold Pau Cubarsí's shot, allowing Merino to tap in the decisive goal.
The Arsenal midfielder said he was delighted to help Spain once again, crediting both preparation and persistence for being in the right place at the right time.
Spain had taken the lead in the 30th minute when Fabián Ruiz converted a rebound, but Belgium equalized before halftime through Charles De Ketelaere, ending Spain's remarkable run of not conceding a goal throughout the tournament.
Merino's late strike sent Spain into its first World Cup semifinal since lifting the trophy in 2010. The victory also set up a highly anticipated clash with France in Arlington, Texas, with both unbeaten teams seeking a place in the final.
Spain coach Luis de la Fuente expressed confidence ahead of the semifinal, describing it as a meeting between two football giants while insisting his side has what it takes to overcome the tournament favorites.
Belgium suffered a major setback in the second half when first-choice goalkeeper Thibaut Courtois was forced off with an injury. Lammens replaced him in his first World Cup appearance but was unable to prevent Merino's late winner after spilling a powerful effort inside the penalty area.
Belgium coach Rudi Garcia praised his players' performance, saying they matched Spain for much of the contest but lacked the fortune needed to defeat a team of Spain's quality. Defender Brandon Mechele also said the squad could take pride in its tournament despite the heartbreaking exit.
Spain extended its unbeaten run in competitive matches to 37 games, while Belgium's 18-match unbeaten streak came to an end.
The match also ended Spain's impressive defensive record after goalkeeper Unai Simón had gone 650 World Cup minutes without conceding. That streak was broken when De Ketelaere headed in Timothy Castagne's cross before halftime.
Belgium was further weakened before kickoff after captain Youri Tielemans suffered an injury during the warm-up, joining defender Amadou Onana on the sidelines, reports UNB.