Serbian footballer dropped from national team for not singing anthem

Serbia lost 2-0 in a friendly against Spain on Saturday, but 20-year-old Serbian midfielder Adem Ljajic committed an offense before the match even began that would get him kicked off the team. According to the Football Association of Serbia, Ljajic breached their code of conduct by not singing the national anthem with his teammates prior to kick off due to "personal reasons." Said the FAS in an official statement(via the Independent):

"Coach Mihajlovic yesterday held a meeting with Ljajic. After hearing Ljajic did not sing the anthem due to personal reasons and that that stance would not change, Sinisa Mihajlovic told the player to return home.

"The door has not been closed forever on the national team but he needs to change his attitude and officially notify Mihajlovic that he has done so.

"Then when his form merits it, he can return."

As the statement implies, this move probably has more to do with his general attitude than just his willingness to sing the anthem. Four weeks ago, Ljajic goaded then Fiorentina manager Delio Rossi after being subbed out of a Serie A match in the first half. Rossi responded by physically attacking him in the dugout -- which simply isn't the type of thing a seasoned manager does just because one of his players gave him a bit of sarcastic applause.

I'm curious how one goes about "officially" notifying their manager that they've changed their attitude, though. A doctor's note? A notarized letter where all the lowercase i's are dotted with smiley faces? A YouTube video that shows him hugging a kitten while singing the anthem? Maybe all three.