Football!

The penalty was 100% clear, and complaints should be directed not at the referee, and not even at the player who committed the foul, but at the pair of center-backs who completely messed up in this match, essentially costing the team two games.

I advise you to rewatch the episode. There was dangerous play from both sides, but the Bayern player had already stopped and was without the ball, therefore he posed no threat to the goal. This is not something that should be called as a foul. I am sure that if this had happened at the other end of the pitch, the referee would have remained silent. Of course, there is no conspiracy to favor teams from the former Soviet Union, but it is financially beneficial for UEFA for the big teams to continue to progress, and it is easier for the referees. This leaves its mark on the decisions in any controversial moments, which is why towards the end of the match the referee started to make fair decisions, because he understood that he would be held accountable for any mistake at the end of the game. Another question is that the Zenit players themselves should understand all this and not give any reason for controversy, because it is always better to start looking for the problem within yourself, and with Toni's return, any negligence is twice as dangerous.
And also, regarding the refereeing, apart from the fact that Arshavin received a yellow card absolutely undeservedly. After Kan was substituted, there was a moment when, during the chaos in the penalty area, the ball went through the German goalkeeper's legs, and the defenders prevented it from going into the goal. I have the impression (although I would like to see a replay) that one of the Bayern players had the ball hit his hand. And according to modern football trends, that is a 100% penalty. And if that is the case, then even a "satisfactory" rating for the referee would be a gift.