Stark failed to regularly deal with injured Barça players

Following last night's UEFA Champions League match between Paris Saint-Germain and FC Barcelona, team responsibles of both involved clubs have voiced public criticism at the German officiating team headed by experienced referee Wolfgang Stark.

fr.r.: Zwayer, Stark faced criticism after the final whistle (c) kicker.de

While PSG's manager Carlo Ancelotti emphasized that the penalty that was awarded to Barcelona in the 89th minute had been "a gift by the referee" to the Catalans (a separate post on this issue will follow during the next days), Barcelona's co-manager Jordi Roura stated that "the official [had] not meant it well for [them]". Among others, the Catalans were annoyed at Stark's dealing with two of their players who were injured and thus needed medical treatment in the same situation. Unfortunately, posting video footage on this scene is impossible due to copyrights owned by UEFA. Therefore, I try to explain the situation to those who have not watched it (minute 76).
Paris S.G. executed a corner kick, the defenders Piqué and Mascherano collided with each other. Stark allowed the play to continue, the ball arrived at a Paris striker a few moments later, who was only not offside as the two injured Barcelona players dissolved it. He nearly scored, goalkeeper Valdés kept the ball, another corner kick came into existence.

At first, one may say that it is quite comprehensible that Barcelona's players heavily complaint about the fact that Stark allowed the play to continue in the heat of emotions. It was also effective from Stark to demonstrate outer strength and determination while facing the furious Catalan players. 

First an important fact: it was no foul committed by a Paris player. Both Barcelona players collided without impact of an opponent.

In compliance with Law 5, the referee has the following duties considering injured players:

• - "Play is allowed to continue until the ball is out of play if a player is, in the opinion of the referee, only slightly injured.

• - Play is stopped if, in the opinion of the referee, a player is seriously injured [UEFA specially put  head injuries and an improved cognition of them as serious injuries on the agenda prior to Euro 2012]."

As the official did not interrupt the play immediately, Piqué and Mascherano (the players who were injured) were the second and third last defender and hence repealed the offside position of the striker who got the ball and nearly scored a goal for PSG.

However, here one must question whether it was sensible to let the play go on at all. Surely, it was a challenging situation for Stark. The ball was quickly cleared out of the box after the corner kick, so that he had to focus on other incidents in this particular moment and had perhaps no eye for both injured players. Here, the additional assistant referee comes into play. He had enough time and a good position to estimate whether it is a serious injury or not. Furthermore, one must take into account that both players repeatedly raised their heads to follow the action and then decided to stay lying down in the penalty area. In a sum, also additional assistant referee Felix Zwayer had basically good reasons to not classify these injuries as serious ones. I however think that nobody would have complaint if, upon consultation with Zwayer, Stark would have stopped the game to quickly allow medical treatment. 

The scene went on though. At this point, the real mismanagement started. Stark asked both players Mascherano and Piqué to leave the pitch after having been treated by doctors. They strongly complaint and even physically obstructed Felix Zwayer during the corner. In general, asking an injured player who received medical treatement to leave the field of play is all right, as Law 5 further defines:

• - "As soon as the referee has authorized the doctors to enter the field of play, the player must leave the field of play [...]. If a player does not comply, he must be cautioned for unsporting behaviour.
• - An injured player may only return to the field of play after the match has restarted. When the ball is in play, an injured player must re-enter the field of play from the touch line. 
• - When the ball is out of play, the injured player may re-enter from any of the boundary lines." 

However, the law furthermore features exceptions, among others, this one, which was implemented prior to the 2010/11 season:

• - "Exceptions to this ruling are to be made only when [...] players from the same team have collided and need immediate attention."

Therefore, Piqué and Mascherano were right when complaining about Stark's ordinance that both have to leave the field of play. As two players of the same team, Piqué and Mascherano of Barcelona, were injured, they should have been allowed to stay on the field of play.

Not only Wolfgang Stark, but also Felix Zwayer (and Jan-Hendrik Salver, the AR) should have been aware of this law. I do not want to imagine the discussions and aftermath of this incident if Paris had scored after the corner kick(s).

Finally, it is disappointing that such experienced officials belonging to the Elite Group and First Group respectively more or less violate or infringe the Laws of the Game on such a level and in such a game.