All quarter-final matches at the French Open have been delayed after heavy rain in Paris in Wednesday, causing huge changes to the tournament’s strict schedule, including Novak Djokovic’s match with Alexander Zverev.

“We regret to announce that, due to poor weather conditions, no more matches will be played today (Wednesday June 5) at Roland Garros,” French Open organizers said in a statement.

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The women’s quarter-finals between defending champion Simona Halep of Romania, who should have faced 17-year-old Amanda Anisimova from the US, and between American player Madison Keys and Australia’s Ashleigh Barty, will now be played on Thursday.

Also among the cancelled quarter-final matches were two men’s singles ties, including the highly anticipated battle between number one-ranked Novak Djokovic and Germany’s Alexander Zverev. Russia’s Karen Khachanov also should have played Austria’s Dominic Thiem on Wednesday but that game will now be moved to Thursday.

Spectators who bought tickets for the cancelled quarterfinals will be allowed to attend the rescheduled games free of charge.