Ronaldo put Portugal ahead in Munich on 15 minutes, but would eventually end up in the losing side as Germany scored four unanswered goals in 25 minutes of play either side of half-time.
Two of those were own goals. Ruben Dias and Raphael Guerreiro both put the ball through their own net within four minutes of each other.
After the break, Kai Havertz extended Germany’s advantage further, before left-back Robin Gosens added a fourth.
Diogo Jota – assisted by Ronaldo – scored what turned out to be a consolation goal on 67 minutes.
The result moves Germany on to three points in Group D – level with Portugal. Both sides know they must avoid defeat in their respective final group games to put themselves in with a stronger chance of qualification.
Hamann criticises Ronaldo
After the game, Hamann – who was working on the game as a pundit for RTE – was disappointed with a piece of showboating that Ronaldo pulled off early on in the game.
The 36-year-old and Germany’s Antonio Rudiger both went in to challenge for the ball, with Ronaldo getting there first.
He flicked the ball up and beyond his opponent, before producing a superb no-look backheel into the path of team-mate Diogo Jota.
Former Liverpool midfielder Hamann, however, clearly wasn’t too impressed with the piece of skill.
He said: “I think it’s nonsense.
“He flicks the ball over, pretends he is going to catch it and backheels it across and looks away. Of course it is [amazing] and we know he can do that.
“I think, in a way, he’s belittling the opposition.
“This is at 1-0 and I’m sitting here while you all rave about it, how good he is. And yes, he is the best, with Messi.
“He looks a fool now because this is 1-0. He does look the fool.
“If you ask the German players, after the game, what they thought of it, they would have noticed that. I tell you now, all of them swill say it may have given us an extra bit of whatever to change things.
“What is he trying to achieve? Maybe this [comeback] is where it all started.”
Portugal are next in Euro 2020 action on June 23 when they take on France in Budapest.
Germany, meanwhile, take on Hungary on the same date and time.
Featured Image Credit: Getty / UEFA