The Portuguese quickly confirmed after securing a place in the final that Romero would feature ahead of the first choice Spaniard in Stockholm.
Romero was handed a place in the starting XI against Southampton as preparation for the clash with Ajax and produced a sensational display between the sticks.
And Mourinho has confirmed that De Gea respects the decision he has made over the Argentine.
“The difficult thing of who is number one and who is number two, who plays and who doesn’t is comfortable for me,” he said. “Because of that personal relationship it is never a problem.
“I never saw two keepers to be so close as friends.
“Normally with the goalkeepers – unless there is a huge difference – when difference doesn’t exist, they are not best friends. They are rivals.
“But they are amazing with each other. Everything is smooth. Everyone accepts my decisions all season. I’m happy with both. And Joel will play the next match because he also deserves it.”
This is what Tata Martino labelled as a “champagne problem” – the conundrum of which keeper you choose – but nobody, especially De Gea, should have ever expected anything else.
The Argentine has seven clean sheets in Europe this season and still hasn’t experienced defeat in any of his 17 appearances. His revival under Mourinho cannot be underestimated; this is somebody who, just last season, looked uncomfortable receiving a back pass.
Now, however, he will rightly start in a European final – something that, not so long ago, would have aroused mass fear amongst supporters.