The Brazilian coach handed the captain's armband to Ronaldo when he took off starting skipper Nuno Gomes late in the game, explaining he wanted to give the Manchester United star a boost after a long season.
"I wanted to motivate him, to give him a little extra oomph to help him forget his tiredness.
"I have five captains, I'm always talking to them. I called them all into my room after Quim's injury and told them what I was going to do."
Ronaldo's assured display cast aside concerns that he may have become distracted by Real Madrid's bid to prise him from Old Trafford.
"I'm happy with what I did today. I'll get better but to be at this stage already is positive," the 23-year-old winger said.
"It was a great team victory, we deserved the win. If we continue like this we can go far at this Euro, but we have to stay calm, we haven't won anything yet."
Pepe, who scored Portugal's first goal, added: "I can hardly describe all the emotion I felt when I scored the goal, especially after one I scored that was disallowed earlier.
"But the important thing was we played like a real team and we knew sooner or later we'd score a goal."
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