Serena Williams will face Danka Kovinic in the first round as the American great begins her final US Open campaign.

It will be a final grand slam for 40-year-old Williams, who has won six singles titles in New York and been a runner-up on four occasions.

Her first singles crown in a major came as a 17-year-old at Flushing Meadows, when she beat Martina Hingis in the 1999 final.

Now the end of a glorious career is beckoning for the 23-time singles major winner, who has also landed 16 doubles grand slam titles.

Kovinic is the world number 80 from Montenegro, with the 27-year-old having only won two matches at the US Open in four previous main-draw appearances.

The winner of that match will likely face Estonian second seed Anett Kontaveit in round two. Kontaveit's first-round opponent will be Romanian Jaqueline Adina Cristian.

Defending champion Emma Raducanu, who was a shock winner last year, faces a tricky first-round assignment against France's Alize Cornet.

Cornet is the tour veteran who beat Iga Swiatek at Wimbledon, ending the Pole's 37-match winning streak, and this will be her 64th consecutive grand slam appearance, a record for WTA Tour players.

World number one Swiatek starts against Italian Jasmine Paolini and could face 2017 US Open champion Sloane Stephens in round two.

Former champion Naomi Osaka, unseeded this year, was paired with Danielle Collins, the 19th seed who was an Australian Open runner-up at the start of the year.

The tournament gets under way on Monday.

Men's defending champion Daniil Medvedev faces American Stefan Kozlov in his opener, while Rafael Nadal, who has not lost a grand slam match all year, faces Australian wild card Rinky Hijikata.

Nadal won the Australian Open and French Open titles before pulling out of Wimbledon ahead of his semi-final against Australian Nick Kyrgios due to an abdominal tear.

That handed Kyrgios a bye through to face Novak Djokovic, who got the better of the Australian, but the Serbian must miss the US Open because his refusal to be vaccinated against the COVID-19 virus meant he would not be allowed to enter the United States.

Djokovic's absence was confirmed shortly before the draw was revealed.

Fast-rising Spanish teenager Carlos Alcaraz begins against Argentina's Sebastian Baez, while fourth seed Stefanos Tsitsipas will face a yet-to-be-determined qualifier.