Last updated on .From the section Tennis

Novak Djokovic playing at the Adelaide International
Novak Djokovic is currently in Australia - 12 months after he was deported from the country

The United States has extended its requirement for international visitors to be vaccine free.

At least 10 April is when proof of vaccine will be required to enter the country.

The Miami Open and Indian Wells are two of the most prestigious tournaments on the tennis calendar.

A year after he was deported from Australia because of his vaccine status, the former world number one is in Australia.

In July, Australia dropped its vaccine requirements, and in November, a three-year visa ban for Novak Djokovic was lifted.

He is through to the second round of the Adelaide International as he builds up to the Australian Open.

It is just one Grand Slam title shy of the men's record of 22 held by Nadal.

He spoke about his experience in Australia in which he was forced to stay at an immigration hotel and he couldn't forget it. It's one of those things that stays with you for the rest of your life.

It was something that I have never experienced before and I hope never again.

Analysis

Russell is a tennis correspondent for the British Broadcasting Corporation.

The back-to-back tournaments in Indian Wells and Miami are some of the most prestigious tournaments in the world.

It is possible that not being able to play in Australia contributed to his loss to Nadal in the quarter-finals of the French event.

If he wins the Australian Open, he could return to the top of the rankings, but if he misses the US tournaments, he could lose up to 2,000 ranking points.

With every extension of the US vaccine requirement, the threat of a missed US Open increases.

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