Ralf Rangnick says he and Cristiano Ronaldo made a joint decision that the five-time Ballon d'Or winner would play no part in Manchester United's FA Cup clash with Aston Villa.
The pair spoke in private on Sunday before United trained at Carrington.
Ronaldo is suffering with some minor problems and the duo both agreed that the 36-year-old should sit out the third-round tie.
"I spoke with Cristiano yesterday before training," said Rangnick. "He told me that he had some problems for the last couple of days, some minor problems. In the end, we decided to not take any risks in a cup game that could easily last 120 minutes."
Rangnick's admission that he spoke to Ronaldo and made the decision with him suggests the German is trying to avoid a problem that, ultimately, cost Ole Gunnar Solskjaer his job.
Is Cristiano Ronaldo the best striker in England? Have your say in the comments.
Solskjaer dropped Ronaldo for United's 1-1 draw with Everton, which went down like a lead balloon.
According to The Sun, the Portugal international was furious with Solskjaer's decision, with a source telling the paper at the time: "Ronaldo was extremely disappointed for being benched.
"Ole presumed that he was tired after the Villarreal game, so he decided to only put him on early in the second half. But Cristiano told him that he will tell him when he isn't fit to play and that he wants to play in every single league game.
"He also told him that he has come here to win trophies and that United need to play their most important players in all of the games."
Sir Alex Ferguson was also overheard questioning Solskjaer's decision, pointing out that a manager worth his salt always starts his best players.
Solskjaer responded to Ferguson's comments at the time, saying: "I'm quite relaxed about it but, of course, it's not really fair on the gaffer that something like this gets broadcast.
"You always have opinions and you speak to people, you speak to people in confidence.
"I disagreed with the gaffer quite a few times and I told my wife quite a few times that I disagreed with him but that never made headlines as a player. I'm sure Sir Alex knows that it doesn't bother me.
"We all want to see Cristiano. We all want to, because he's unique, he's different, he's had a career and everyone wants to come and watch him. But the plain fact of it is he cannot play every single game that we play, that's just physical nature, human nature.
"But he knows how difficult this job is anyway, the gaffer. He didn't always play the same eleven. He took some risks at times to rest Ryan Giggs, Wayne Rooney or David Beckham, the best players that we had. Sometimes it works, sometimes it didn't."
Rangnick's decision to drop Ronaldo for this Monday's clash against Villa is unlikely to cause the same uproar experienced by Solskjaer following the Everton game.
But it is interesting all the same that Rangnick discussed his decision with Ronaldo first, and then informed the press of the process to drop the star ahead of the Villa clash.