World number five Daniil Medvedev claimed his first clay-court win of the year with a straight-set victory over Italy's Lorenzo Sonego to reach the third round of the Monte Carlo Masters.
Medvedev, who has won four hard-court titles this year, beat Sonego 6-3 6-2.
Clay is not Medvedev's preferred surface, with the 27-year-old Russian - seeded three in Monte Carlo, never having won a title on it.
"I always struggle on clay, every match is a struggle," he said.
Medvedev, who will play Germany's Alexander Zverev on Thursday, added: "There's no rhythm on clay, every bounce is a bad bounce and even when it's good you're expecting a bad bounce."
World number 16 Zverev beat Spain's Roberto Bautista Agut 6-4 6-4 in just his second match on clay since suffering a serious ankle injury in the French Open semi-final against Rafael Nadal last year.
Also on Wednesday, fourth seed Casper Ruud of Norway beat Dutchman Botic van de Zandschulp 7-5, 7-6 (7-1) and will play Jan-Lennard Struff after the German, 100th in the world rankings, upset Australia's world number 19 Alex de Minaur in straight sets.
Jannik Sinner will take on Poland's Hubert Hurkacz in the third round after the Italian's opponent Diego Schwartzman was forced to retire with a shoulder injury.
Belarussian Ilya Ivashka, who beat Britain's Dan Evans in the previous round, fell 7-6 (7-2) 6-2 to his brother-in-law Karen Khachanov, with the Russian ninth seed now facing compatriot Andrey Rublev, who overcame Spain's Jaume Munar.
Lorenzo Musetti will face world number one Novak Djokovic after a comfortable win over fellow Italian Luca Nardi 6-0 6-0, while Chile's Nicolas Jarry set up a third-round tie with Greece's second seed Stefanos Tsitsipas.
Jiri Lehecka of the Czech Republic beat Bulgaria's Grigor Dimitrov and will meet Taylor Fritz in the last 16 after the American eighth seed got past Switzerland's Stan Wawrinka 7-6 (12-10) 6-2.