Granit Xhaka found himself at the centre of another controversy involving Serbia after donning a shirt with 'Jashari' on the back following Switzerland's 3-2 win in Doha on Friday.
Xhaka produced a man of the match display as the Swiss hit back from 2-1 down to secure second place in Group G and advance to a last-16 clash with Portugal on Tuesday.
But his actions after the final whistle could attract the attention of FIFA.
In the post-match celebrations, Xhaka put on a shirt carrying the name 'Jashari'. Asked afterwards what it meant, the Arsenal midfielder claimed it was for Switzerland squad member Ardon Jashari.
However, the name carries significance in other ways with Adem Jashari a late founder of the Kosovo Liberation Army, a Kosovo Albanian separatist group that fought for independence from the former Yugoslavia.
Xhaka is of ethnic Albanian heritage linked to Kosovo, which declared independence in 2008 but has not been recognised by Serbia.
Asked about the shirt afterwards, Xhaka said: "There's no political background to it whatsoever.
"Ardon is part of our squad and we spend a lot of time together. I told him if we won I would wear his shirt."
Xhaka was a key figure throughout a feisty encounter. He also prompted a second-half melee that saw the Serbia bench encroach on to the pitch after making a crude gesture, thought to be in the direction of substitute goalkeeper Predrag Rajkovic, whose personal life has been the subject of speculation this week.
Switzerland boss Murat Yakin said he will "wait and see" if action is taken against Xhaka.
"We will enjoy this moment, it cost us a lot of emotions and energy. It was a fair match," he said.
"Before the game a lot of people were talking about the situation but we were able to face that challenge.
"We are happy we are moving on. Everything else is speculation and we will wait and see."
On the incident involving Rajkovic, Yakin added: "What I saw was a Granit Xhaka who was focused fully on football and performed very well. I saw the players from Serbia crossing the line, and others trying to calm them down. It was a normal exchange."
It is not the first time Xhaka has been embroiled in controversy against Serbia. At the 2018 World Cup in Russia, he and Xherdan Shaqiri were fined after crossing their hands to mimic the eagle displayed on the Albanian flag in Switzerland's 2-1 win.
Shaqiri also played his part in Switzerland's victory here, scoring the opening goal at Stadium 974, but appeared annoyed to be taken off after 69 minutes.
"No-one likes to be subbed," Yakin said. "Every player wants to play the whole game, but it's part of my responsibility to protect players. He scored his goal and had a great assist.
"The substitutes brought great energy and I thought they did well."
The flashpoints overshadowed a wonderful game with Switzerland's greater composure at key moments proving decisive.
Serbia coach Dragan Stojkovic praised his players but lamented the fact so many were struggling for fitness throughout their time in Qatar. He also insisted he had no intention of resigning.
He said: "We are not happy with the result but, given the problems we faced from our arrival here and the injuries we had to contend with, it was too much for us to cope with.
"The guys put up a fight but at this level that is not enough.
"As for my future, in March we start the qualifiers for the European Championship and we have a great desire to qualify."
Stojkovic claimed not to hear any of the chants that prompted an announcement over the public address system asking fans to refrain from discriminatory songs or gestures, thought to originate from sections housing Serbian supporters.