Spain booked their place at Euro 2020 as they came from behind to draw 1-1 with Sweden, but United will be more concerned with the health of their goalkeeper, who limped out of the action.
The 28-year-old goalkeeper hobbled off after an hour of the game, and there are now big concerns in the United camp that he will be unable to play against Liverpool at Old Trafford in a huge game on Sunday afternoon.
In an innocuous-looking incident, De Gea immediately grabbed the back of his thigh after clearing a backpass from his own player, and there are fears he may have pulled his hamstring.
He sat on the ground in his six-yard box before making his own way off the pitch accompanied by the Spanish medical team. United boss Ole Gunnar Solskjaer will be hoping the injury is not serious and will be anxiously waiting for an update on his fitness.
Spain did not comment after the game, but even if it is not serious, the keeper has to be rated as an early doubt for the visit of Jurgen Klopp's men.
Meanwhile, Inter Milan have given a fresh update over the fitness of Alexis Sanchez, who is on loan at the San Siro from United.
Sanchez has been diagnosed with a dislocated ankle and tendon damage, picked up while on international duty with Chile, and a decision will be made today on whether the player needs to undergo surgery.
"Alexis Sanchez underwent medical tests earlier (on Tuesday) morning at the Humanitas Institute in Rozzano," Inter said on their official website. "Results revealed a joint dislocation in his left ankle which has caused damage to the peroneus longus tendon."