Fourth-seeded Casper Ruud extended his winning streak on clay to nine matches to reach the third round at the Monte Carlo Masters on Wednesday. (More Tennis News)

The 2022 French Open runner-up was made to work hard by Botic van de Zandschulp in his opening match at the Country Club before winning 7-5, 7-6 (1) on the slow surface.

Ruud has won the past two clay events he has played, in Gstaad last July and in Estoril last week.

“It is never easy to start at a new tournament and against a player I have lost to before,” said Ruud, who fell to his Dutch opponent in Miami last month. "Sometimes it is a little tricky playing someone you recently lost to, like Not again', but in this case I was a bit happy because I felt like some unfinished business from the Miami match.”

Ruud, who saved one set point in the second set, will next be up against Jan-Lennard Struff, who defeated 14th-seeded Alex de Minaur 6-3, 6-2.

After struggling with consistency at the start of the year in the wake of his best season, Ruud has found his confidence back on his best surface.

"It felt great last week in Estoril,” he said. “It felt very comfortable. Today was at times a very good match, but at times a little rusty. There are a lot of positives to build on.”

Also advancing to the third round were seventh-seeded Jannik Sinner, 13th-seeded Alexander Zverev and No. 16 seed Lorenzo Musetti, who got past fellow Italian Luca Nardi 6-0, 6-0. The quick win earned Musetti the right to take on top-ranked Novak Djokovic.?

Rafael Nadal and second-ranked Carlos Alcaraz pulled out of the tournament last week. Nadal has won it a record 11 times, including an Open Era record streak of eight consecutive titles from 2005-12. But the 22-time Grand Slam champion has been sidelined with a left hip flexor injury since the Australian Open.