Australian tennis superstar and defending world No.1 champion Ashleigh Barty has pulled out of the French Open citing coronavirus concerns and a lack of preparation.

Her decision not to defend her French Open title is a massive blow to the grand slam event.

“It has been a difficult decision to make but unfortunately I will not be competing in Europe this year,” Barty said in a statement on Tuesday.

“Last year’s French Open was the most special tournament of my career so this is not a decision I have made lightly.”

“I now look forward to a long pre-season and the summer in Australia,” Barty said.

It is Alex de Minaur’s first grand slam quarter-final. Photo: AAP

Meanwhile, Australian young gun Alex de Minaur has moved into his first grand slam quarter-final after beating Vasek Pospisil in straight sets at the US Open in New York.

De Minaur has a golden opportunity to progress even further in a draw depleted by Novak Djokovic’s dramatic disqualification on Monday after Roger Federer and defending champion Rafael Nadal didn’t even start.

He is only focusing on his quarter-final, against second-seeded Australian Open runner-up Dominic Thiem, a 7-6 (7-4) 6-1 6-1 winner over Canadian Felix Auger-Aliassime.

“Nothing changes.” he said. “I’ve just got my match ahead of me and I think it (Djokovic’s elimination) affects more the people on that side of the draw, to be honest.

Barty’s ‘difficult decision’

Uncomfortable about travelling during the coronavirus pandemic and with her preparations hampered by COVID-19 restrictions in Australia, Barty is the biggest name to opt out of the major, which is set to start in Paris on September 21.

The 24-year-old said there were two reasons behind her decision – the health risks as well as her limited training without coach Craig Tyzzer “due to the state border closures in Australia”.

Barty had already skipped the US Open, along with Australian men’s star Nick Kyrgios, and hasn’t played since the Doha semi-finals in February.

Tweet from @ashbarty

She said she planned to continue training at home in Queensland to prepare for the summer of tennis, with the Australian Open still scheduled to go ahead in Melbourne in January.

“It has been a challenging year for everyone and although I am disappointed on a tennis front, the health and wellbeing of my family and my team will always be my priority.

“Thank you to my fans for your continued support. I can’t wait to play for you again.”

-with AAP