It is likely that Novak Djokovic will not be able to play in at least three of the four Grand Slam tournaments this year.
The world number one lost a public fight to play in the Australian Open this month because the country has very strict rules about coronavirus.
In the end, Djokovic's visa was revoked and he didn't win an appeal. He was sent back to Serbia, where he couldn't defend the title he has won in each of the last three years.
The 20-time Grand Slam champion could also be in for more bad news later this year, because the rules in France and New York don't allow players who haven't been vaccinated to play.
There was a vote in France's lower house that went 215 to 58 in favour of giving the vaccine pass final approval. It will keep people who haven't been vaccinated out of restaurants, sports arenas, and many other places. Djokovic might not be able to play at Roland Garros because of this new law. It will apply to everyone over the age of 16, and the law will take effect soon.
New York rules also say that unvaccinated athletes can't play in sports events in the state.
Wimbledon is the only Grand Slam tournament that Djokovic will be able to play in this year if he doesn't get a shot of the flu.
In 2013, Djokovic won three of the four Grand Slam tournaments. He lost the US Open final in the final, which meant that he didn't get a calendar slam because it was the last one.
Serbs Roger Federer and Rafael Nadal have both won 20 Grand Slams.