Tennis champion Marion Bartoli has questioned the prestige of the upcoming US Open due to the number of players withdrawing due to COVID concerns.

The women's draw has been hardest hit with six of the top 10 players in the world deciding to not compete in the tournament in New York.

World no.1 Ash Barty was the first and it then became a flow-on effect - with world no.2 Simona Halep the most recent to withdraw.

US Open defending champion Bianca Andreescu has also decided to withdraw from the event, putting her health first instead of defending her title.

In the men's draw, world no.2 Rafael Nadal is out, Roger Federer is still recovering from surgery and was ultimately going to miss the event anyway due to injury.

Bartoli, who won Wimbledon in 2013, told TennisMajors.com that this year's event cant be compared to previous years.

"The players who will win the US Open under these circumstances will know that they didn't really win the US Open," she said.

"You can't really say that you won a Grand Slam when you have 20 out of the top 32 players are not competing.

"It's another stuff when they lose, if they can be in the main draw, lose, and you happen to play another player, that's part of the sport,"

"But when they are not showing up at all, I don't think it's possible to call it a Grand Slam."