London, Jun 16 (IANS): Kiki Bertens, former world No.4 and the Netherlands's highest-ranked player in WTA history, said on Wednesday that this year would be her final competitive tennis season.

The 29-year-old Kiki, who had reached the French Open semi-final in 2016 and the Wimbledon quarter-final in 2018, has won 10 singles and 10 doubles titles in her career.

In an Instagram post, Kiki said a combination of last year's Covid-19 outbreak and a lingering Achilles injury had forced her to bring a premature end to her competitive career.

"For me, if Covid didn't come maybe I could continue for two to three more years, I have no idea. But when you're in the rhythm of doing something, it's easy for me and I can just keep on going, no matter how long," said Kiki.

Kiki was not thinking about retirement when the 2020 season began as she had won the Madrid Open -- her biggest title of her career -- the previous year and had reached a career-high ranking of No.4.

She began 2020 on a positive note, making the quarter-finals in Brisbane and pre-quarterfinals at the Australian Open.

"But then Covid came and everything changed. With the unknown, it was tough to go out there and practice every day," she said.