A coronavirus scare forced the main draw to be postponed yesterday, while play at warm-up tournaments in Melbourne was suspended.

A 26-year-old man, who was working at the Grand Hyatt Hotel where hundreds of players were staying, tested positive for COVID-19.

As a result, more than 500 players, officials and support staff who were deemed to be close contacts were forced to self-isolate until they produce a negative test result.

The positive test raised concerns that the first Grand Slam event of the year could be in jeopardy.

Australian Open organisers later announced that all tests conducted on quarantine participants yesterday have returned negative results.

The negative tests allowed for play to resume at warm-up events and the tournament draw to take place.

Serena Williams prospects of winning an eighth Australian Open title appear more challenging, with the American great suffering both an injury scare and a potentially tough draw.

Williams announced her withdrawal from the semi-finals of the Yarra Valley Classic due to a right shoulder injury today.

Her potential path to the Australian Open title could include a last-16 match with Belarus’ Aryna Sabalenka, a quarter-final with second seed Simona Halep of Romania and a semi-final against Japan’s third seed Naomi Osaka.

Williams is seeking to secure a record-equalling 24th major title of her career, while she could become the first player to win a Grand Slam singles title in four different decades.

Top seed Ashleigh Barty features on the other half of the draw, with the Australian only able to face Williams in the final.

Barty suffered elimination in the semi-finals last year, losing in straight sets to Sofia Kenin of the United States.

A rematch at the same stage of the tournament could be possible, with fourth seed Kenin seeking to defend her title.

Eight-time champion Novak Djokovic will begin as the favourite in the men’s singles, but faces a potentially tricky run to the final.

Germany’s Alexander Zverev is among the opponents the Serbian star could face on route to the final, with last year’s runner-up Dominic Thiem of Austria a potential semi-final opponent.

Second seed Rafael Nadal could move clear of Switzerland’s Roger Federer for most Grand Slam men’s singles titles, should he triumph in Melbourne.

The 20-time Grand Slam winner’s projected path to the final includes a quarter-final meeting with Greece’s Stefanos Tsitsipas, before a semi-final with Russia’s Daniil Medvedev.

COVID-19 has dominated the build-up to the event, with 72 players unable to leave their hotel rooms for two weeks after flying in on planes where positives cases were later detected.

It was previously announced that up to 30,000 spectators will be permitted to attend the opening eight days of the Australian Open, with this number falling to 25,000 per day from the quarter-final stage.

The tournament is due to begin on Monday (February 8).

The Grand Slam was pushed back by three weeks to accommodate the quarantine periods for players.