An Alessandro Del Piero stunner and Amauri header earned Juve the win and Ranieri said: "Constructive criticism is good, but my worry is when I get the feeling some of the attacks are premeditated.
"The important thing is that the lads believe and always keep hold of that confidence. We are not in great shape with so many injuries, but nobody can doubt the heart, fight and quality of my squad.
"We were fortunate to take the lead early on and could therefore contain Real Madrid and focus on the counter."
Ranieri added: "Our trouble is we have quality, but we can only express it with a great physical performance. I am convinced that once we get our fitness levels back and can raise the tempo consistently, we will be a very difficult team to beat."
Juve's celebrations after the final whistle were extremely enthusiastic and significant after the recent newspaper talk of a split locker room and disagreements with the Coach.
"Perhaps it is good that this match and the celebrations are the outer confirmation of what we have all been saying. This is a very united squad and I know the club and players are close to me. Only together can we get out of this situation."
Ranieri also reserved a thought for the bus of Juventus fans that crashed on the way to the stadium, killing two and injuring more than 20.
"I wanted to give my condolences to the fans who died, as knowing they came here to enjoy themselves and gave their lives for that makes us feel terribly small."