The Australian Open will start on February 8, three weeks later than scheduled, the ATP Tour said in releasing an update of its calendar for 2021 revising the first seven weeks of the season.
The start date of the main draw of the year's first Grand Slam was originally slated for January 18 and organisers Tennis Australia have been in drawn-out negotiations with local government over COVID-19 health measures.
Tennis Australia was not immediately available for comment.
The ATP release said men's qualifying for the Australian Open would take place in Doha from January 10-13 before players relocated to Melbourne to enter quarantine.
The ATP tournament scheduled to take place in Adelaide has been moved to Melbourne to be played in the week commencing January 31, alongside another men's tournament in the city.
A shortened version of the ATP Cup men's team tournament will take place in Melbourne from February 1-5 before the Grand Slam begins on the following Monday.
The ATP season will open with tournaments in Delray Beach, Florida and Antalya in Turkey before preparations for Melbourne Park begin.
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