Often when a side complains about an official following a defeat, there's at least a slight note of sour grapes involved.

AC Milan, though, certainly have reason to feel aggrieved by the performance of Turkish referee Cuneyt Cakir in their 2-1 Champions League defeat against Atletico Madrid in the Champions League on Tuesday evening.

Per The Sun, Milan are so upset at a number of the decisions made by Cakir at the San Siro that the club is reportedly set to lodge an official complaint with UEFA over his showing.

A viral Twitter video from user @Futball_Karim has highlighted some of the inconsistencies in Cakir's officiating on the night, as well as a number of outright errors he appears to have made. All in all, it's tough to argue that Milan do not have a strong case.

The match got off to a strong start for the home side when Rafael Leao gave them the lead after 20 minutes. Just a short while later, however, Milan were reduced to 10 men when midfielder Franck Kessie was shown a second yellow card for catching Marcos Llorente on the foot while challenging for the ball.

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Minimal contact was made and it did seem like a harsh booking in the circumstances. With that said, the decision becomes even harder to rationalise when you watch the highlights package and see Rodrigo de Paul get away with a similar challenge on Sandro Tonali later in the game.

The compilation also draws attention to several instances where Cakir seems to ignore foul play from the Atletico players. The official also fails to check a potential handball from the visitors inside their own penalty area, much to the frustration of the home fans.

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Milan managed to hold their advantage until six minutes from the end when Antoine Griezmann equalised for Atletico. As the match headed into stoppage time, though, the hosts looked set to hold on for a deserved point.

Hopes that Milan might take something away from the match were majorly dented when Cakir awarded Atletico a penalty a stoppage time. The official pointed to the spot after penalising Milan's Pierre Kalulu for handball.

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Replays, however, appeared to show that the ball had first struck the arm of Atletico's Thomas Lemar.

In theory, the whole situation should have been cleared up by VAR, but no intervention was made, meaning that Cakir did not review the incident on the pitchside monitors.

Predictably, Luis Suarez fired home the penalty to give Atletico all three points.

You can check out Cakir's disasterclass below. 

Of course, even if Milan are successful with their complaint, the result of the match will stand. Cakir, though, appears to have had such a howler here that it absolutely warrants further review.

Even allowing for the fact that the compilation has been put together from a Milan perspective, the standard of refereeing on display still seems to have been well below the level expected in Europe's top club competition.

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