The Portuguese suggested his side took Galatasaray more seriously than the Spanish media prior to the match, and insists the foul for Sergio Ramos' booking was not intentional
Cristiano Ronaldo, Karim Benzema and Gonzalo Higuain struck the goals to put los Blancos in complete control of the tie going into the second leg in Istanbul, but Mourinho reserved praise for his team's defensive efforts.
"I think we defended better than we attacked," he told Sky Sports after the match. "In attacking terms, we lost the last ball, the last pass. We had easy transitions, three against three, three against four, so we could have scored more goals. But I think from a defensive point of view, we had a very good analysis of the situation and the team played very well."
Mourinho then suggested that the Spanish media had played down the strength of their opponents in the build-up to the encounter, insisting his own team never allowed themselves such a mindset.
"We played seriously. The Spanish press were not quite so respectful to Galatasaray, but we were respectful to them," he went on. "We know that they are a great team with good strikers who are dangerous on every attack and we prepared very well from a defensive point of view.
"I know that if we score a goal [in Istanbul], they have to score five. The result is very good, but in football, I have seen so many incredible things that nothing can surprise me and Istanbul is a difficult place to play. They have players with a lot of experience, great character, great personality."
Sergio Ramos picked up a cheap yellow card for kicking the ball away in the closing minutes, ruling him out of the return leg but ensuring he is free to take part in the semifinals, but Mourinho dismissed the idea that the booking was part of his plans.
When asked if the yellow card was helpful to his side, he said: "Not much, because I lost Xabi Alonso and I was going to play Pepe in midfield in Istanbul, but when Sergio got a yellow card he left me with a problem to resolve."
The former Chelsea boss also revealed he spoke with Didier Drogba and Wesley Sneijder after the match.
"I was with him [Drogba] at the end of the match, and with Wesley. They are family. They weren't during the 90 minutes, but they are family," he added.