At Wimbledon this summer, neither Russian nor Belarusian players, such as Daniil Medvedev and Victoria Azarenka, were welcome after Russia's invasion of Ukraine.
In the US Open, the last grand slam tournament of the year, however, they are welcome under a neutral flag.
Some of the stars are on Wednesday in a charity tournament in New York that coincides with Ukraine's Independence Day.
The money that comes in will go to the Ukrainian war effort.
Among star names such as Rafael Nadal and Coco Gauff, another stands out: Victoria Azarenka from Belarus.
The participation of the former world number one has caused Ukrainian players to see red.
- When me and Lesia Tsurenko (Ukrainian tennis player) found out that there will be representatives from Belarus or Russia at this event, I immediately said that I will not participate, says Ukrainian tennis player Marta Kostjuk to the BTU site.
She continues:
- First of all, no one has asked the Ukrainian players if we wanted some of these players present.
Of course, nobody wants that.
It's Ukraine's Independence Day, but what Ukrainians think isn't interesting, right?
- I don't understand why they invited Victoria Azarenka, says Kostjuk.
The US Open starts on Monday.
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