The U.S. Open tennis championship is now underway with top athletes from around the world in attendance. But there’s one noticeable absence: Novak Djokovic. The Serbian star and runner-up in last year’s U.S. Open — and who just won Wimbledon last month — was not allowed to compete this year because he was not permitted to fly into the United States. Why? Because, as he’s not vaccinated against COVID-19, he’s in violation of the Center for Disease Control and Prevention’s vaccination rule requiring foreigners flying into the country to be fully vaccinated.

Despite having played in last year’s U.S. Open at the same location and having competed in other championships around the globe, the U.S. would not let Djokovic in to compete this year over his COVID-19 vaccination status.

This prompted prompted Fox News White House correspondent Peter Doocy to press White House press secretary Karine Jean-Pierre on vaccination requirements for people flying into the U.S. but not for people entering the U.S. illegally.

“How come migrants are allowed to come into this country unvaxxed but world-class tennis players are not?” Doocy asked.

Jean-Pierre responded, “This is a CDC requirement for foreign nationals — this is something they decide.”

That interaction appeared all over social media and on multiple news outlets, with many people claiming that migrants don’t need to get a COVID-19 vaccine. But U.S. policy does require all foreigners and migrants traveling through ports of entry — whether by land, sea or air — to be fully vaccinated. The Department of Homeland Security announced the policy in January.

“Starting on January 22, 2022, the Department of Homeland Security will require that non-U.S. individuals entering the United States via land ports of entry or ferry terminals along our Northern and Southern borders be fully vaccinated against COVID-19 and be prepared to show related proof of vaccination,” DHS Secretary Alejandro Mayorkas said.

Migrant children are exempted from the rule.

The new policy, however, does not have an impact on the thousands of migrants every week who cross illegally or are never stopped. It is those now hundreds of thousands of migrants that critics have blasted the Biden administration for failing to stop and thereby skirt the vaccination mandate.