Josip Simunic has been charged by FIFA over his post-match chants in the wake of Croatia's World Cup qualification.
The defender took the microphone in the aftermath of Tuesday's 2-0 play-off win over Iceland and addressed Croatia's supporters with a cry of: "For the people."
That phrase has links with the pro-Nazi regime which ruled the country during World War II, although Simunic has fiercely denied his actions were politically motivated.
Simunic's denial did not spare him a fine by local public prosecutors, and now the 35-year-old is facing the possibility of FIFA sanctions.
A statement from football's governing body read: "We can confirm that disciplinary proceedings have been opened concerning the case."
Simunic's statement, released the day after the game through his club Dinamo Zagreb, read: "The thought that anyone could associate me with any form of hatred or violence terrifies me.
"I did nothing wrong. I'm supporting my Croatia, my homeland. If someone has something against it, that's their problem."