Top seeds Alcaraz and Swiatek advance at Madrid Open

WATCH:Carlos Alcaraz defeats Grigor Dimitrov in the 2023 Madrid Open third round match highlights.

Carlos Alcaraz made it easier on himself this time at the Madrid Open, reaching the round of 16 with a straight-set victory over Grigor Dimitrov on Sunday.

After struggling in a three-set win in his opener against unseeded Emil Ruusuvuori, Alcaraz improved to get past the 26th-seeded Dimitrov 6-2, 7-5 and stay on track to defend his title on home soil.

Alcaraz was still not at his best but sealed the victory by converting four of his six break opportunities against Dimitrov. The second-ranked Spaniard was broken only once, in the second set. He finished with 16 winners and four unforced errors.

"We didn't do some things well in that first match and it was clear that we had to get back to doing what we know, which is to go on attack," Alcaraz said.

It was the 17th straight win for the 19-year-old Alcaraz on home soil. He won the Barcelona Open for a second consecutive year earlier this month.

He next faces 13th-seeded Alexander Zverev in a rematch of last year's final in the Spanish capital.

"I have great memories from last year in the final but obviously I have to be really focused in that match," Alcaraz said. "I know that Sascha is a really good player, a really aggressive one with good serves. I have to show all my skills."

Iga Swiatek continued to cruise in the women's draw, reaching the round of 16 with a comfortable 6-3, 6-2 win over Bernarda Pera.

The world No. 1 conceded only one break point and converted four of the 13 that she earned against the 32nd-ranked American.

Swiatek had beaten Julia Grabher by the same score in her opening match in Madrid. The Polish player has won six straight matches in her clay-court season while dropping only one set.

"I wouldn't say it was easy," Swiatek said. "Every match is tricky here. I'm happy that I'm getting my rhythm. Playing against a lefty is never easy ... but I'm pretty happy that I was disciplined and focused."

Swiatek has lost only five games in each of her first two matches this week, dropping serve only once in each match.

This is her second appearance in Madrid, having missed the tournament last season because of a right shoulder ailment. She lost to then-No. 1 Ashleigh Barty in the last 16 in 2021.

Swiatek will next play 16th-seeded Ekaterina Alexandrova, who came from behind to defeat 22nd-seeded Zheng Qinwen 5-7, 6-4, 6-2.

Third-seeded Jessica Pegula had to work harder on her way to a 6-4, 7-6 (2) win over Marie Bouzkova. The American saved 12 of the 14 break opportunities that she conceded against her 31st-ranked opponent.

"It was definitely a long, physical game," Pegula said. "It's always hard to play Marie. We always have tough, long matches. I knew it was going to be very difficult."

Two-time Madrid Open champion Zverev cruised past qualifier Hugo Grenier 6-1, 6-0 in less than an hour.

"Today I felt great," Zverev said. "Maybe Hugo was a bit nervous, first time in the third round at a Masters and that is big for any player. In general I am happy that I kept my composure and that I am through."

Zverev, who had 26 winners and broke Grenier's serve six times, won his Madrid titles in 2018 and '21. He is 21-3 in the tournament, having reached the quarterfinals in all five of his previous appearances.

Fifth-seeded Andrey Rublev improved to 10-1 on clay this season with a 6-2, 7-5 win over Yoshihito Nishioka. Rublev, who reached the quarterfinals in Madrid last year, won the Monte Carlo Masters two weeks ago.

He next faces Karen Khachanov, the 10th-seeded player who defeated home-crowd favorite Roberto Bautista Agut 7-5, 4-6, 6-3 by winning the final three games in a match that lasted almost three hours