PARIS — American Sofia Kenin has lost in the fourth round at the French Open to Maria Sakkari of Greece, 6-1, 6-3.

At No. 4, Kenin was the highest-seeded player left in the tournament. She was the runner-up at Roland Garros last October, and was seeking her second major title.

Sakkari, seeded 17th, advanced to her first career Grand Slam quarterfinal and earned her sixth win against a top-20 player this year.

Kenin lost serve six times and had 32 unforced errors to 15 for the steady Sakkari.

Earlier, Novak Djokovic rallied from a two-set deficit to win for the fifth time in his career. He beat 19-year-old Lorenzo Musetti of Italy, who retired with an injury two games from defeat in the fourth round at the French Open.

Musetti took a medical timeout after the fourth set, briefly left the court, and conceded after losing the next four games. The score was 6-7 (7), 6-7 (2), 6-1, 6-0, 4-0. Djokovic lost only 10 points in the third set and four in the fourth, and won the final 13 games.

Seeded No. 1, Djokovic remained in contention for his second French Open title, and his 19th at a Grand Slam. He improved to 34-10 in five-setters.

The Serb advanced to the Roland Garros quarterfinals for the 15th time. He’ll next play another Italian, No. 9-seeded Matteo Berrettini, who advanced when Roger Federer withdrew.