World number one Novak Djokovic

The 22-time Grand Slam winner, 35, had applied for special permission to enter the US because he is not vaccinated against Covid-19.

BBC reports the US requires international visitors to be vaccinated and proof will be required until at least 10 April.

Djokovic missed last year's US Open because of his vaccination status.

"World number one Novak Djokovic has withdrawn from the 2023 BNP Paribas Open. With his withdrawal, Nikoloz Basilashvili moves into the field," organisers said in a statement.

The 34-year-old showed no sign of rust or mental baggage from his Australian Open saga, producing a typically clinical display to ease into the second round.

It was Djokovic's first match this year after his hopes of playing at the Australian Open were dashed after he was deported following an 11-day saga revolving around his decision not to have a COVID-19 vaccination and a controversial exemption.

The Serb will meet Polish seventh seed Hubert Hurkacz in the last four on Saturday.

Djokovic and Fritz traded fierce ground strokes in the first set before the 20-times major winner broke serve at 3-4. Fritz broke back immediately but Djokovic's supremacy from the back of the court finally told as he clinched the opener in 38 minutes.