German World No. 3 Alexander Zverev cruised into Monte Carlo Masters last 16 after outplaying Argentina's Federico Delbonis 6-1, 7-5 on Wednesday.

After top seeds Carlos Alcaraz and Felix-Auger Aliassime both crashed out, Zverev took to the court as the highest-ranked player remaining in the tournament.

He lost the first four points of the match but breezed through the first set in just over 20 minutes and dropped only three points on serve.

The 24-year-old was tested by Delbonis in the second, fighting back from 2-4 down and winning the next 11 points to move within a game of victory before converting his third match point.

"It's not bad for a change of surface after Miami, you have to take that into consideration a little bit. I'm happy with the win," said Zverev, who lost to Norwegian Casper Ruud in the quarterfinal of the hardcourt event.

The German's best run in the Principality tournament was in 2018 when he reached the semifinals, while he exited last year in the third round.

"I know that I have to play much better," Zverev added. "This is the only Masters on clay that I haven't won. I'm very motivated to do that and hope I can show it on court this week.

Earlier, unseeded American Sebastian Korda mastered the windy conditions to topple world No. 11 Alcaraz 7-6(2), 6-7(5), 6-3 in an entertaining battle that lasted just over three hours, with both players struggling for rhythm.

"After losing to a Spaniard in Indian Wells and serving for it, it was nice to get a victory today," said the 21-year-old Korda, who pushed Rafa Nadal to a third-set tiebreak at the California tournament. "It was a crazy match!"

Korda will take on compatriot and Indian Wells winner Taylor Fritz after he beat former U.S. Open champion Marin Cilic 6-3, 4-6, 6-4 while Zverev will face Pablo Carreno Busta, who advanced after Alexander Bublik retired in the third set.

Miami Open champion Alcaraz followed top seed, Novak Djokovic, out of the tournament and was joined by Auger-Aliassime as the Canadian world No. 9 fell 6-2, 7-6(2) to an inspired Lorenzo Mussett in front of a raucous crowd.

Last year's finalist Andrey Rublev prevailed 2-6, 6-1, 6-4 over Alex de Minaur, fourth seed Ruud saw off Holger Rune 7-6(5), 7-5 and Jannik Sinner got past Finnish qualifier Emil Ruusuvuori 7-5, 6-3 in other second-round matches.