Caroline Wozniacki failed to advance past the semifinals in the seven tournaments she has played this season. (Robert Ghement/EPA)

The French Open announced Tuesday on Twitter that former world No. 1 Caroline Wozniacki has withdrawn from the Grand Slam clay court tournament that begins Sunday in Paris, citing a right ankle injury.

It was another hit to the star power for the season’s second major, coming just eight hours after world No. 8 Belinda Bencic of Switzerland withdrew with a back injury.

Wozniacki, 25, has not competed since losing in the Round of 32 at the Miami Open in March. The Dane announced her withdrawal in mid-April from the clay court tuneup tournaments in Madrid and Rome and has failed to advance past the semifinals in the seven tournaments she has played this season.

In early May, Wozniacki, now ranked 34th in the world, posted a tweet with a photo of her on the tennis court with what appears to be a heavily wrapped right ankle.

In addition to Wozniacki and Bencic, 2009 U.S. Open champion Juan Martin del Potro of Argentina announced earlier this month he will skip the French Open to focus on the grass-court season as he continues to rehab from his wrist injuries.

The major tournament could also be without two-time French Open champion Maria Sharapova. The 29-year-old Russian is awaiting a ruling from her doping case after Sharapova announced in March that she tested positive for meldonium, a banned substance.

The draw ceremony for the French Open is Friday.