Already on a yellow, Ronaldo was sent off after it was judged he kicked Gabi in the face. You can see the challenge below.
It's a bit inconclusive to determine just how much Ronaldo connected. But what that doesn't show is what led up to the incident. Spanish football expert Graham Hunter was upset with the foul by Gabi that had preceded Ronaldo being given an early exit:
This is arguably the nadir for what has been a disappointing season for Ronaldo and Real Madrid as a whole. The club finished second to Barcelona in La Liga, was humbled by Borussia Dortmund in the semifinal of the Champions League and lost to Atletico for the first time since 1999.
There's the ever-so-slight chance that Ronaldo could leave the Santiago Bernabeu this summer. It would represent a poor move on the part of the star player. More likely, the speculation is done by Ronaldo in order to give him more leverage in future contract talks.
Say what you want about Ronaldo, but there's no questioning his desire and motivation. There's no getting around the fact he's an extremely driven player. You don't become one of the best in the world simply by relying on your God-given talent.
Maybe he could spend a couple of years among the best in the world without working too hard off the pitch, but he's won the Ballon d'Or in 2008 and finished second on four other occasions. That's a sustained level of dominance.
Of course, he could make more money at PSG or maybe even at Manchester United if he doesn't get a pay raise from Madrid. If salary was his sole motivation, though, he would have fallen off like the original Ronaldo, Adriano and Ronaldinho as he began earning hundreds of thousands of pounds a week.
Ronaldo has an insatiable desire to be the best in the world and win the Champions League title with Real Madrid, which would be the historic "La Decima."
Sure, he went through his "sad" period earlier this season, but there should be no question as to his future with the club. If anything, this loss to Atletico should embolden his desire to remain at Real Madrid.
If in the minute chance the Copa Del Rey final does in fact prove to be one of Ronaldo's last matches with the club, he'll forever have that be what many will remember of his time at the Bernabeu. Plus, he will have left without bringing the 10th European title to Madrid.
There have been plenty of legends to come through the club. You've got the likes of Alfredo Di Stefano, Figo, Zinedine Zidane, Brazilian Ronaldo, Iker Casillas, Emilio Butragueno, Fernando Hierro, Raul and Hugo Sanchez. That's just a snippet of the greats who have worn the white shirt.
Ronaldo is in rarefied air at Madrid. All of the names, and yet he could become the best yet. He's scored an unfathomable 146 goals in 135 league matches for Madrid and 35 goals in 40 European fixtures.
If he leaves without winning the Champions League, he'll still be considered a great player. His career narrative will always carry around his European failures, though. Throw in the Copa Del Rey final, and you've got a poor end to what has been a fantastic run of form for Ronaldo in Spain.
He can't possibly go out that way.