The Madrid Open has been cancelled due to the rise of COVID-19 cases in the Spanish capital.
The clay-court tournament, which was scheduled for September 12-20, was seen as an important event for men's and women's players to prepare for the French Open, which begins on September 27.
The only top-level clay-court event leading into the French Open will now be the Internazionali BNL d'Italia in Rome on September 20.
"As an act of responsibility in view of the current situation caused by COVID-19 and having thoroughly evaluated the circumstances that the pandemic continues to generate, it has been decided that 2020 Mutua Madrid Open will not take place this year," organisers said in a statement.
Both the ATP and WTA Tours released a joint statement saying the decision was taken in line with local authorities due to "health and safety concerns" and they were reassessing the calendar for the rest of the year.
"We would like to recognise the efforts of the tournament organisers who have gone to great lengths in exploring all options to run this year's tournament, despite the many challenges presented by COVID-19," they said in a statement.
"Both tours are assessing updates to the 2020 provisional calendars in regards to events following the U.S. Open, and an update will be published in due course."
Spain was one of the worst-affected countries when the pandemic first hit Europe earlier this year and has seen a rise in cases recently.
World No 1 Novak Djokovic is the defending champion at the event which was originally scheduled to be played in May.
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