The WBA has banned Russia's flag, anthem and national symbols - with the country not allowed to be named on fight night in Las Vegas - in response to the invasion of Ukraine.

However, Russian professional boxers including Bivol have been allowed to carry on fighting under these constraints.

The Mexican anthem was played for Álvarez before the fight, as was the American anthem with the event held in the United States, but there was no Russian anthem for Bivol and he indeed entered the ring without a flag being displayed.

Dozens of Mexican flags adorned T-Mobile Arena and one was prominently displayed in Álvarez's corner, with the bout taking place two days after the Cinco de Mayo holiday, which is traditionally a major celebration of Mexican-American culture.

All three judges scored the fight 115-113 in Bivol's favour after he landed considerably more punches than Álvarez and dominated proceedings.

Despite fighting sans national symbols, Bivol has been labelled "the pride of Russian boxing" by RBF secretary general Tatyana Kiriyenko as the organisation sought to champion the 31-year-old's win.

"I am filled with joy and pride," Kiriyenko said.

"My sincere congratulations to Dmitry Bivol and his team. 

"I just want to thank Dima for this fantastic performance. 

"He acted simply superbly, showed an excellent school of boxing, was focused all the time, adhered to the plan clearly and disciplined and listened to his corner."

Kiriyenko went on to add that "our entire boxing community congratulates our award-winning athlete on this success."

According to Russian state news agency TASS, Bivol expressed surprise at being introduced as a fighter who trains in California, as opposed to coming from St Petersburg or Kyrgyzstan.

"Although I don’t blame the organisers, I treat them with understanding, but for me the main thing was the fight," Bivol said, per TASS.

"It’s nice when you represent your country, but I think everyone understands everything."

Kyrgyzstan-born Bivol's victory was a shock one, despite Álvarez stepping up to light-heavyweight for only the second time in his professional career.

The loss is Álvarez's second and first unanimous points defeat, with the Mexican notoriously difficult to beat on the judges' scorecards in Las Vegas, where he controversially drew with and then defeated Kazakhstan's Gennady Golovkin, an Olympic silver medallist, in results that were widely disputed.

Bivol, a runner-up at the Kazan 2013 Universiade, remains unbeaten as a professional.

Before the fight, Ukraine's former world heavyweight and Olympic champion Wladimir Klitschko called for Russian boxers to be banned from competing at all levels.

"Every Russian representative in this case needs to be sanctioned, because this way we show to Russia that the world is against this senseless war and that there’s no good in this war," Klitschko told the BBC, claiming Bivol should "absolutely not" be allowed to fight Álvarez .

Bivol, who was not asked about Russia in the post-fight interview, said before the event that he felt it was "sad" politics and sport were mixing.

Critics of a blanket ban on Russian athletes from international competition - as has been recommended by the International Olympic Committee (IOC) - argue it is unfair to punish individual athletes for the actions of a state.

However, comments such as those from Kiriyenko will be held up by advocates as an example of Russian athletes being used as a propaganda tool.

The International Boxing Association (IBA) the global governing body for amateur boxing, has banned competitors from Russia and Belarus from its events.

The IBA, which has had its IOC recognition suspended, is led by a Russian, Umar Kremlev, who is a former RBF secretary general.

Kremlev is up for re-election later this month.

At least 3,309 civilians have been killed in Ukraine since the Russian invasion began February 24, supported by Belarus, according to the United Nations, although the true figure is believed to be far higher.

More than 5.7 million refugees have fled Ukraine.

Russia has been accused of committing a genocide by Ukrainian authorities, with mounting evidence that civilians have been murdered indiscriminately in some areas. 

Some estimates put the combined military death toll above 20,000.