Having missed two matches with a hip flexor issue, the 36-year-old frontman returned in Wednesday’s 3-1 Premier League win at Brentford.
Ronaldo made headlines with his reaction to being taken off in the second half by interim boss Ralf Rangnick who has revealed the forward might be absent entirely on Saturday.
“Cristiano is a question mark because he has a problem with his neck,” he told MUTV.
“He received treatment yesterday for two or three hours and we will have to wait to see how he feels today.
“Edi (Cavani) hasn’t been training with the team yet and will hopefully resume training today and then we’ll take the final decision after the training session today, if he will be available for the game tomorrow.”
Ronaldo has been a hot topic after making it clear to all that he did not appreciate being substituted against Brentford.
Rangnick immediately attempted to diffuse the matter publicly and again said he understood the player’s frustration, but he would prefer it not to be played out in public.
“I didn’t at all see or interpret that as if he was challenging me,” Rangnick said. “He just showed, maybe too emotionally, that he was not happy to be replaced.
“But this was not the first time. I think if you have a look at the moments when Sir Alex (Ferguson) replaced him or other coaches, (Maurizio) Sarri or whoever, replaced him in the past his reaction was pretty similar.
“This shows that in the end it has got nothing to do with the manager at the time managing the team. It’s about his own ambition and his own desire to stay on the pitch.
“But, again, it’s a team sport and for us it’s important for us that we get the most out of each game, the maximum points. In the end then it’s a decision of each manager.
“What do we need right now in order to secure the game, to make sure that we win the game? And what kind of weapons do we need on the pitch to be able to score on the counter-attack?
“I’m not somebody who says afterwards ‘listen, everything was perfect, we did it right’. But in this case all the things that I hoped that would result from that decision they were confirmed in the end.
“I think if at one stage Cristiano will also be maybe a manager himself in a couple of years, or maybe as late as 10 years if he’s playing another five years, he will have the same experience himself.
“Again, I don’t blame him for that but obviously any manager, I think, would wish that it shouldn’t be too emotional, even more so in front of the TV cameras.
“I don’t think that this will be to the benefit of anyone – not to his benefit, not to the benefit of the team-mates or the others.
“In the end, it’s an emotional game, players are being emotional and I didn’t take it personal at all.”