Novak Djokovic has criticized Wimbledon's decision to ban players from Russia and Belarus from competing in the 2022 tournament amid Russia's ongoing invasion of Ukraine.
The All England Club announced on Wednesday that players from both countries won't be allowed to compete in this year's tournament.
Djokovic called the decision "crazy" when speaking to reporters after defeating Laslo Djere in the round of 16 at the Serbia Open.
"I know how much emotional trauma [war] leaves," he said. "In Serbia we all know what happened in 1999. In the Balkans, we have had many wars in recent history. However, I cannot support the decision of Wimbledon, I think it is crazy.
"When politics interferes with sport, the result is not good."
Djokovic isn't the only one to oppose the decision. The ATP and WTA, the governing bodies for men's and women's tennis, both released statements after the decision was made.
"Discrimination based on nationality also constitutes a violation of our agreement with Wimbledon that states that player entry is based solely on ATP Rankings," the ATP said, according to Reuters.
The WTA said it is "very disappointed" by the decision:
"Individual athletes should not be penalised or prevented from competing due to where they are from, or the decisions made by the governments of their countries. Discrimination, and the decision to focus such discrimination against athletes competing on their own as individuals, is neither fair nor justified."
According to Reuters, this marks the first time players have been banned from competing at Wimbledon on the grounds of nationality since Japanese and German players were barred in the immediate aftermath of World War II.
Elina Svitolina, who is from Ukraine, told BBC Radio 5 Live Breakfast that Russian and Belarus players should be allowed to play if they "speak up" and denounce the Russian government.
"If players don't speak out against the Russian government then it is the right thing to ban them," she said.
Daniil Medvedev, Andrey Rublev, Karen Khachanov, Aslan Karatsev, Ilya Ivashka, Anastasia Pavlyuchenkova, Daria Kasatkina, Veronika Kudermetova, Aryna Sabalenka and Victoria Azarenka are among the notable players who won't be able to play at Wimbledon.
Russia's military invasion of Ukraine began on Feb. 24. The United Nations has confirmed at 2,345 civilian deaths and 2,919 injuries since the start of the invasion, but the death toll is likely higher with a delay in reporting, per CNBC's Amanda Macias.