Belgium won 1-0 over Portugal in the Euro 2020 last 16 on Sunday, with Thorgan Hazard firing in a spectacular winner in the 42nd minute.
The Red Devils withstood intense late pressure from Portugal to held out for a spot in the last eight where they will face Italy.
But Belgium may have to take on the Azzurri without Manchester City midfielder De Bruyne, who went off on 48 minutes with an ankle issue.
Real Madrid playmaker Hazard also had to be substituted late with fears of a hamstring strain.
“We are going to need 48 hours to find out the extent of the injuries,” Belgium head coach Roberto Martinez said. “We will go back to Belgium and make the scans tomorrow.”
“Kevin De Bruyne… it was a very bad tackle. We have no diagnosis from the medical department. Eden Hazard is more muscular.”
Martinez was delighted by his side’s resilience to hold out the Portuguese.
“It wasn’t just about how good we could be, it was about how we could adapt to what Portugal do the best, which is do exactly what they need to do to win,” he said.
“That is why they are the current champions and winners of Nations League. They have incredible experience and know how to take those moments to hurt you.”
Portugal boss Fernando Santos bemoaned the defeat, insisting his side deserved to win.
“The Belgians had six shots and one on target,” he said. “We had 29 and couldnt score once.
“We didnt let them use their most dangerous weapons. It was a shot from outside the box from their left-back who doesnt even do this.
“None of us can feel anything but proud for these players. We didnt win, but we deserved to win. No team in the world can say they are better than Portugal.”