The merits of the Fifa World Player of the Year need little amplification outside Mourinho's office. But to those who argue that Ronaldo's best work has not always been seen on European fields, the evidence of Tuesday night puts the boot into their position.
When Sir Alex Ferguson met him last summer to put the case for his return to Manchester, the future he outlined embraced occasions such as these, when a young team with him at the hub would bestride the great stadiums of Europe and boss the show.
The joy of six goals experienced by Madrid against Real Betis last week would not sustain him long if Madrid were coming second in Europe to the team he left behind. The evidence before the Italian court on Tuesday points to a greater rate of plunder at Old Trafford by a team maturing into perhaps the best of all Ferguson's creations.
Proud was the word Ronaldo chose to describe how he felt about United's display. Yes, a goal would have helped ease nerves for the return leg in a fortnight, but he is not losing sleep about the outcome.
"We played nice football and showed we are a great team. If we play like that in Manchester I think we win. I'm very proud. The lads played brilliant, like a real team. The only bad thing is we didn't score, but that is football. We respect them but in my opinion we have a better chance at Old Trafford because we have a better team."
Mourinho shifted down through the gears at a rate of knots in the retreat from his pre-match bombast. He contemplates the return leg grateful for the agility and reflexes of his goalkeeper, Julio Cesar, and the comfort inherent in keeping United goalless. You can wager a euro that he won't be talking up Ibrahimovic with quite the same enthusiasm.
The morning after the night before Mourinho's oration had morphed into a confessional, striking a more conciliatory tone. "They are a very quick team and we don't have these characteristics, The reason I lost only once against Manchester United is that I understood this immediately.
"If they had scored in the first half, the situation would have been harder for us and, for this, it is not an easy decision to make to sit deep and try to block them. If we had played further up the field, then it gives us more options in attack, but it leaves us more room behind."
Mourinho is in something of a jam. The margin for interpretation that allowed him to negotiate, creatively, the territory between perception and reality before this tie are shrinking. You can't talk up a performance like Inter's or talk down a display like United's. Sometimes it is better to say nowt and go quietly. Not Mourinho's way, of course.
Goallessness is not a state that can detract from Ferguson's achievement in Milan. Too often in the past he has deferred to the opposition with some tactical innovation or other and more often than not ended up emasculating his own team. Mourinho used the Barcelona example last year when United progressed to the final in a most un-United-like way, voluntarily conceding territory and possession.
Inter, and by extension Mourinho, were embarrassed in the first half, caught in a blizzard of perpetual passing. Ferguson said his team had matured. More importantly, so has he, demonstrating that at the age of 67 you are not too old to learn.
The conviction with which his team play in the Premier League was duplicated on the highest stage. Mourinho is running out of sticks with which to beat his old foe ahead of the second leg at Old Trafford on Wednesday week. Doubtless he'll think of something.