Goals from Endrick and Alexis Ciria put Real Madrid 2-0 up inside the first half at the Worthersee Stadion in Klagenfurt, Austria, before Moise Kean pulled one back for Fiorentina right on the stroke of half-time and completed his brace after the break to make it 2-2, with a moment of silence held before kick-off in memory of Franco Baresi.
Speaking to RMTV afterwards, Mourinho said he had been struck by the different physical states within his squad.
"I liked everything. I got to the dressing room and saw on my phone 'a Madrid of two faces.' It was a Madrid of three faces: fresh, tired and super tired. The fresh one played very well. The 2-1 scoreline at half-time is very tight. It's a first half of very high quality. The second half becomes more physical against a typical Italian team. They put pressure on us," he said.
"Then with Moise Kean, he played in the box with two 18-year-olds who had a great game, even if they're not at the level of a beast like Kean. The face I also liked was the super tired one, which knew how to control the game.
"Dumfries and Endrick trained for three days and played more than 70 minutes. A fantastic effort that has meaning. I liked everything. I thanked Grosso."
Asked about his approach to team selection given the squad's uneven fitness levels, Mourinho was clear that Real Madrid's standards do not lower for a friendly.
"It's Madrid with the players we have. As I told the lads before the game, Real Madrid is Real Madrid even in a friendly. You have to look for progress but also dignity. I had to put out the players I had available, like Trent and Dumfries.
"We don't just train for one match. On the pitch the team knows what it has to do. Joan and Mario have a fantastic future, even physically they've shown real class. Of the seven available, two had trained for three days. Then there's Espi, who is still waking up from a dream and had only trained for an hour. Today he helped us. I'm happy. I'd like to have three weeks of work with other players. Vini, Bernardo, Brahim are coming... that's how it is," he said.
Asked how it felt to be back in the Real Madrid dugout, Mourinho was typically wry.
"Nothing yet. The good ones are still missing," he said, laughing.