Novak Djokovic is on the entry list for this week's Masters 1000 event at Indian Wells, although organisers have said they are unsure whether the world No 2 would be permitted to enter the United States.
The 20-time Grand Slam winner has refused to obtain a Covid-19 vaccine and previously said he was prepared to miss tournaments as a consequence. His unvaccinated status has already caused issues for Djokovic, who was infamously deported from Australia on the eve of the Australian Open after the government ultimately refused to accept his medical exemption.
Similar to the entry rules for Australia, the CDC (US Centers for Disease Control and Prevention) website as of March 3 indicated non-US citizens who are not immigrants must show proof of vaccination against Covid-19 to travel by air to the United States.
The Indian Wells men's draw on Tuesday showed he had a first-round bye.
"Novak Djokovic is on the tournament entry list, and therefore is placed into the draw today. We are currently in communication with his team," Indian Wells organisers wrote on Twitter. "However, it has not been determined if he will participate in the event by getting CDC approval to enter the country."
Djokovic was unable to compete at the Australian Open after immigration authorities detained him on January 6, prompting a legal rollercoaster ride over the country's Covid-19 entry rules that led to the cancellation of his visa later that month.
Indian Wells, often referred to as tennis' "fifth major," is expected to welcome a full house after it was cancelled in 2020 and moved to October last year due to the pandemic.
The women's first round begins Wednesday while the men's starts Thursday.
With former world No 1 Roger Federer out of the tournament as he recovers from knee surgery and Djokovic previously presumed absent, Spaniard Rafael Nadal could be the only member of the 'Big Three' to compete at Indian Wells, where he will be among the favourites to win a fourth title. Nadal is on a 15-match winning run to start the 2022 season, collecting titles in Melbourne and Mexico either side of his record-clinching 21st major at the Australian Open.
Djokovic eventually got his season underway at the Dubai Duty Free Tennis Championships last month, where he lost to Czech qualifier Jiri Vesely in the quarter-finals.
The defeat meant the 34-year-old Serb lost his world No 1 ranking to Russian Daniil Medvedev, who claimed his maiden major title at the US Open in September and is the top seed at Indian Wells.
France loosened Covid-19 restrictions earlier this month, with vaccine passports no longer mandatory as of March 14, opening the door for Djokovic to mount a title defence at Roland Garros beginning May.
