Cristiano Ronaldo Injury News Questioned By His Sister & Man United Legend Roy Keane

Manchester United forward Cristiano Ronaldo did not feature in Sunday's 4-1 defeat at Manchester City after being ruled out with hip flexor injury.

Ralf Rangnick broke the news of the 37-year-old's absence ahead of the game.

"Cristiano had some problems with his hip flexor on Friday," United manager Ralf Rangnick revealed before kick-off.

But former United captain Roy Keane was not convinced and suggested that there may be another reason why Ronaldo was left out.

"I just don't like it when the manager talks about this hip flexor, I don't get it," Keane said on Sky Sports, as quoted by the Daily Mail.

"We talk about Ronaldo being some sort of machine. He's very rarely injured and then every now and again he comes out with something like that and says 'hip flexor'. It doesn't add up to me."

Keane was still not convinced after the game. "There's something going on in the background," he added. "There is something amiss."

Seven-time Premier League winner Keane was not the only person who doubted Rangnick's story.

Ronaldo's sister Katia Aveiro liked an Instagram post which included a rant denying that the former Real Madrid forward had been left out because of an injury issue.

"Cristiano Ronaldo is not injured and he is not ill," read the caption of an Instagram post published by a user named 'cr7.0_lendario', who has over 500k followers.

"The man is 100 per cent. Good morning to you who, like me, are sad and angry because Rangnick decided to ruin our Sunday by taking CR7 out of the derby against Manchester City simply for tactical reasons, to defend himself more in the game."

Rangnick was informed in a post-match interview that some people had doubted his explanation behind Ronaldo's absence.

"I have to believe my medical department," Rangnick replied.

"Our doctor came to see me Friday morning before training and said Cristiano could not train because of some problems with his hip flexor and the same Saturday."

Ronaldo had played the full 90 minutes eight days earlier when United limped to a 0-0 draw with Watford at Old Trafford.

He has faced City 15 times in his career, winning nine of those matches and scoring five goals.

Without him, United were thrashed 4-1 on Sunday.

Kevin De Bruyne scored twice in the first half, either side of a goal by Jadon Sancho.

Riyad Mahrez added two more goals in the second half as City extended the gulf between themselves and their neighbors to 22 points.

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Cristiano Ronaldo pictured during Manchester United's 0-0 draw with Watford

IMAGO/Nick Potts