The Portuguese superstar was sent off during his side's 2-0 win over Valencia, putting his participation against Manchester United in serious doubt
Cristiano Ronaldo stole all of the headlines on the second night of the Champions League, as he was sent off during Juventus' 2-0 win over Valencia on Wednesday.
The Portugal international was shown his very first red card in Europe's premier club competition after he appeared to pull the hair of defender Jeison Murillo.
Ronaldo was astonished at the decision to the point that he was even reduced to tears as his first return to Spain since his departure from Real Madrid turned sour.
Indeed, he had to be helped from the turf after collapsing upon seeing the card, and took a number of minutes to leave the pitch.
UEFA assess cases on an individual basis, though they do institute an automatic one-match suspension for a straight red dismissal.
It remains to be seen, however, if that suspension will be lengthened.
What did Ronaldo do to get sent off?
After running into the box, Ronaldo and Murillo clashed, the defender claiming he was kicked by the 33-year-old.
Ronaldo reacted to that, raising his arm in protest, before appearing to scratch Murillo's head with his hand.
Murillo then squared up to the forward, and players from both teams were forced to intervene.
Referee Felix Brych consulted the official behind the goal, and a decision was taken to send Ronaldo off, leaving him in tears.
You can watch the incident in the videos above.
Will Ronaldo miss Juventus' game against Man Utd?
A fairytale return to Old Trafford is on the cards at October 23, but Ronaldo will now be sweating over the prospect of missing a reunion with his former employers.
He will certainly miss Juve's next encounter, against Young Boys, on October 2 in Turin.
Ronaldo cannot appeal his ban, but faces an anxious wait to see if that suspension will be extended by UEFA.
Were it to be extended to two games, he would sit out the Old Trafford clash, and a three-game ban would see him fail to face United at all, either in Manchester or Italy.
Former Premier League referee Mark Clattenburg believes Ronaldo's red card was harsh - he claims he would have shown both Murillo and the Portuguese a yellow, and awarded Valencia a free-kick - and thinks a one-match ban will suffice.
Writing in the Daily Mail, he said: "The contact looked very slight and I cannot see how the additional assistant, standing some 20 yards away, could deem it violent conduct.
"If I had been officiating this game, I would have given Valencia a free-kick and shown a yellow card to each player. Ronaldo will serve a one-match ban but anything more would be harsh."
When will we find out how long Ronaldo is banned for?
The case will be dealt with by the UEFA Control, Ethics and Disciplinary Body (UCED) on Thursday, Sept. 27. It will then be announced exactly how many games Ronaldo will be banned for.