Ronaldo made his first appearance of pre-season as United were held to a 1-1 draw by their Spanish opponents at Old Trafford.
The five-time Ballon d'Or winner started the match but was brought off at half-time after a tense touchline interaction with manager Erik ten Hag during the first period.
Rather than returning to the dugout to join his teammates, Ronaldo was spotted leaving the stadium before the end of the match.
Diogo Dalot, who was not part of the matchday squad, also left early.
Ronaldo is set to avoid punishment for his premature exit but his behaviour at the weekend has been noted by United.
"It is not a good look to leave early when you have been involved in the squad," a club insider told The Sun.
"It is different if you are up in the stands and not involved.
Not even waited for the final whistle 😮💨 pic.twitter.com/jraOWdoPd5— Gaz (@CantonaManc) July 31, 2022
"You would expect someone who has played in the game to be in the changing rooms at the end to listen to the manager's thoughts.
"Also a lot of people were there to see him and he was not even involved in the clapping of the fans after the final whistle."
Ronaldo's early exit has fuelled the speculation surrounding his future.
Last month, Ronaldo informed United of his intention to leave the club this summer in order to play Champions League football.
He subsequently missed the club's pre-season tour of Thailand and Australia as well as last week's friendly against Atletico Madrid, before finally returning to the team on Sunday.
But United are adamant Ronaldo will not be sold this summer, with Ten Hag insisting the Portugal captain remains part of his plans for the upcoming season.
It is unclear if he will be involved when United kick off their Premier League campaign at home to Brighton on Sunday.
Featured Image Credit: Alamy
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