Serena Williams pulled out of the French Open on Wednesday because of an Achilles injury.

The 23-time Grand Slam champion said she had a short warmup and decided she couldn't continue. She had been scheduled to play Tsvetana Pironkova in the second round at Roland Garros.

“I think I need four-to-six weeks of sitting and doing nothing, at least two weeks of just sitting down,” Williams said.

Serena Williams of the U.S. plays a shot against Kristie Ahn of the U.S. in a near-empty center court Philippe Chatrier in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Monday, Sept. 28, 2020. (AP PhotoAlessandra Tarantino)

Serena Williams of the U.S. plays a shot against Kristie Ahn of the U.S. in a near-empty center court Philippe Chatrier in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Monday, Sept. 28, 2020. (AP PhotoAlessandra Tarantino)

Williams said her ankle didn't have time to recover after the U.S. Open.

Williams added she “more than likely” won’t play another tournament this year, saying she was “struggling to walk, which is a tell-tale sign that I should try to recover.”

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Serena Williams of the U.S. serves against Kristie Ahn of the U.S. in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Monday, Sept. 28, 2020. (AP PhotoAlessandra Tarantino)

Serena Williams of the U.S. serves against Kristie Ahn of the U.S. in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Monday, Sept. 28, 2020. (AP PhotoAlessandra Tarantino)