Simona Halep's participation at the French Open hinges on an ultrasound on her ankle on Saturday.

The Romanian remains favourite for the title at Roland Garros despite tearing a ligament in her right ankle at the Internazionali BNL d'Italia last weekend.

She may not take to the court for her first-round match with Jana Cepelova, though, should her injury not recover in time.

Halep was out on the practice courts on Friday to test her ankle and she says it continues to improve, but ultimately a scan will determine whether she enters the main draw.

"Today is much better," she told a media conference. "Actually, today was the first time when I was running on court when I played some points.

"It's getting better.

"Tomorrow [Saturday] I have another ultrasound to see if the ligament is still broken or it's fixed.

"The last ultrasound said it's just two or three millimetres broken. At the beginning it was much more. I feel that I will play, but I still wait for tomorrow and then I will decide.

"I will do everything I can to start this tournament as good as I can, to be able to play this tournament first, and then we will see what is going to happen."