Madison Keys reached her first French Open quarter-final with a 6-1 6-4 win over Romania’s Mihaela Buzarnescu.

American 13th seed Keys, the 2017 US Open runner-up, broke serve in the second and sixth games before taking the first set with a powerful forehand.

She sealed the win with an ace on her third match point.

Sloane Stephens beat Anett Kontaveit 6-2 6-0 to set up a potential semi-final meeting with Keys, whom she beat in the final at Flushing Meadows.

“I was really pleased to get out and play some good tennis,” said the US Open champion.

American Stephens will face the winner of second seed Caroline Wozniacki’s fourth-round match against Russia’s Daria Kasatkina, which takes place later on Sunday.

Keys will play Yulia Putintseva in the last eight after the Kazakh beat Czech Barbora Strycova 6-4 6-3.

“I’m really excited to be in my first quarter-finals in Paris,” said Keys. “I lost to my friend Sloane in the US Open final last year but I hope for big things here.”

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