A scintillating strike from Thorgan Hazard was enough to knock reigning champions Portugal out of Euro 2020 Sunday.
The win earned Belgium a blockbuster quarterfinal with Italy.
Hazard's swerving shot before half-time sealed a 1-0 win for Belgium and settled a scrappy contest in Seville that never really lived up to its billing as the stand-out tie of the last 16.
But it could prove a statement victory for Belgium, whose chief concern now will be the fitness of Kevin De Bruyne and Eden Hazard, who both hobbled off injured and will undergo scans Monday.
De Bruyne suffered an ankle injury while coach Roberto Martinez said Hazard's problem was "more of a muscle feeling."
Cristiano Ronaldo tested Thibaut Courtois with a dipping free-kick in the first half but the 36-year-old neither broke the international goals record nor added to his five for the tournament.
Raphael Guerreiro went closest to a late equalizer when his shot came back off the post, one of 29 shots Portugal had, six of them on target.
But before the late rally, Belgium was the braver, more fluid team and Martinez hailed his side's fighting spirit to hold on.
"We showed our talent in the first half and in the second half we showed an aspect that wasn't there two or three years ago," said Martinez. "This is what a winning team needs."
For all the superstar names on the pitch, it was Eden Hazard's less-heralded brother Thorgan who proved decisive, the Borussia Dortmund winger who Eden once said had even more talent than him.
"In these games, if you have a chance you have to have a go," Thorgan said. "It went in, with a bit of luck and it was the goal that got us through. It's a dream for me."
Portugal, meanwhile, stuck to the defensive approach that served them so well in France five years ago but has perhaps been outgrown by a side that now boasts some of the most creative technicians in the world.
"I think it's an unfair result but they scored and we didn't," said Portugal coach Fernando Santos.
Eden Hazard started in Belgium's front three again after playing 90 minutes against Finland on Monday. Portugal's Diogo Dalot came in at right-back for the injured Nelson Semedo.
Eden Hazard skied an early shot over after a neat exchange with Romelu Lukaku while Diogo Jota skewed wide, slipped in down the left by the impressive Renato Sanches.
Ronaldo cut an isolated figure up front, his every touch booed early on by the Belgian fans, who then cheered when he was robbed of the ball before being bumped to the ground by Thomas Meunier.
The closest Ronaldo came to an all-time record 110th international goal was a dipping free-kick from 30 yards which Courtois parried away while at the other end, Lukaku was a more dynamic force.
One scintillating break saw Lukaku tear through Portugal's midfield and with his shirt being pulled behind him, he was just lacking the final pass to Hazard.
An untidy game found its moment of clarity in the 42nd minute. It started with Courtois coolly evading Ronaldo's press before more excellent work from Lukaku allowed De Bruyne to switch left to Thorgan Hazard.
He cut in and ripped a swerving shot that rocketed towards the center of the goal before swerving right and past Rui Patricio, who was too slow to adjust.
Belgium played with more verve after half-time and looked set to take charge.
But De Bruyne's injury checked their rhythm and Portugal came again, Jota firing over and Joao Felix, on as a substitute, heading into the hands of Courtois.
Tempers flared as a crescendo of collisions incensed the crowd and left Pepe lucky only to be booked after he led into his challenge with his arm.
Portugal finally had to push and in a wild last 10 minutes, Guerreiro went closest to an equalizer, his shot hammering against the post. Belgium did just enough.
