PARIS (CNN) – The highly anticipated tennis clash between Serena Williams and Maria Sharapova at the French Open will not happen after all. The 36-year-old American pulled out of the tournament on Monday because of an arm injury.

The 23-time grand slam winner had played herself into form through three rounds in her grand slam comeback. But she took to the main Philippe-Chatrier court on Monday to let the crowd know that she could not compete. Williams said that she could not physically serve with the pectoral injury, adding that she felt the injury during her third-round singles match against Julia Goerges.

The U.S. star will have an MRI scan on Tuesday.

“I unfortunately been having some issues with my pec muscle … right now I can’t actually serve, so it’s actually hard to play when I can’t physically serve,” said Williams.

The French Open marked Williams’ third tournament of 2018 — and first since March — after she gave birth to daughter Olympia in September. None of those tournaments came on clay.

The withdrawal means that Sharapova, who held a 2-19 record against Williams and last beat her 14 years ago, moves into the quarterfinals against either Garbine Muguruza or Lesia Tsurenko.

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