Carlos Alcaraz and Iga Swiatek both moved into the last 16 at the Madrid Open with straight-set victories.
Spanish defending champion Alcaraz, who turns 20 on Friday, beat Bulgaria's Grigor Dimitrov 6-2 7-5 in the men's event.
He will face two-time champion Alexander Zverev of Germany for a place in the quarter-finals.
World number one Swiatek continued her run in the women's competition with a 6-3 6-2 victory over Bernarda Pera.
She plays either China's Qinwen Zheng or Ekaterina Alexandrova of Russia in the next round in Madrid.
Alcaraz was briefly troubled when 31-year-old Dimitrov broke for a 4-2 lead in the second set but the Spaniard wrapped up victory in 90 minutes, making just four unforced errors.