World number one Carlos Alcaraz cruised into the last 16 of the Miami Open with victory over Dusan Lajovic.
The Spanish defending champion, 19, won 6-0 7-6 (7-5) to set up a meeting with American Tommy Paul.
Alcaraz, who has won 16 of 17 matches this year and has not dropped a set in his last two tournaments, needs to win the title to stay top of the rankings.
Elsewhere, women's ninth seed Belinda Bencic was beaten 7-6 (10-8) 6-3 by 18th seed Ekaterina Alexandrova.
But after a number of upsets on Saturday, there were straightforward wins for men's seeds Andrey Rublev, Holger Rune and Taylor Fritz.
Russian sixth seed Rublev beat Serbia Miomir Kecmanovic 6-1 6-2, while Rune, the seventh seed from Denmark, won 6-4 6-2 against Diego Schwartzman of Argentina.
Rune will play Fritz in the next round after the American ninth seed beat Canadian Denis Shapovalov 6-4 6-4.
In the women's draw, Elena Ryabkina edged out Paula Badosa 3-6 7-5 6-3, Bianca Andreescu beat Sofia Kenin 6-4 6-4, but 17th seed Karolina Pliskova lost 6-1 6-2 to fellow Czech Marketa Vondrousova.