Defending champion Iga Swiatek reached the quarter-finals of the French Open on Monday with a 6-3, 6-4 victory over Ukrainian teenager Marta Kostyuk. The eighth seed from Poland has won 22 straight sets at Roland Garros and will take on Greek World No. 18 Maria Sakkari for a place in the last four. 

Sakkari knocked out last year’s French Open runner-up Sofia Kenin earlier in the day, leaving Swiatek as the highest-seeded player remaining in the draw.