Roger Federer made a difficult start to his claycourt season with a 7-6, 7-6 second round victory over Italian qualifier Andreas Seppi at the Monte Carlo Masters Series on Tuesday.
Former world number one Marat Safin was knocked out of the tournament when he lost 0-6, 7-6, 6-4 to Belgium's Kristof Vliegen in the second round.
Federer will take on South Korean Hyung-taik Lee, who beat Russian 13th seed Mikhail Youzhny 6-4, 6-3, for a quarter-final spot.
Following an early exchange of breaks, both players held serve to force a tiebreak which Federer won 7-4 when Seppi sent a forehand long.
Federer, who slumped to back-to-back defeats by Argentine Guillermo Canas in the Indian Wells and Miami Masters Series, saved two break points in the sixth game of the second set and the players headed to another tiebreak which Federer won 8-6.
"It's always difficult to start a claycourt season especially against a qualifier," Federer said in a courtside interview.
"I am very happy. The conditions were perfect, it was not too hot, not windy and I am looking forward to my next match."
Earlier, Frenchman Richard Gasquet battled into the second round with a 7-5,,6-7, 7-6 victory over Fernando Verdasco.
The 11th seed wasted five match points in the second set before ending the left-handed Spaniard's resistance in three hours 20 minutes.
Gasquet will take on Slovakia's Dominik Hrbaty, who saw off Spaniard Albert Portas 7-6, 7-5.
GASQUET BATTLES THROUGH
Following a sluggish start, the French number one clinched the first set on Verdasco's serve with a trademark winning crosscourt backhand.
Gasquet was forced into a tiebreak in the second set which he lost 14-12 as Verdasco saved the five match points.
In a sloppy deciding set where there were three breaks of serve, Gasquet clinched victory 7-3 in a tiebreak.
"I ran out of gas in the second set and I have to say the Davis Cup defeat against Russia hurt me a lot," Gasquet said in a courtside interview.
"But it is a beautiful tournament here and I had no choice but to win this match."
Spaniard David Ferrer strolled into the second round with a 6-3 6-1 victory over Frenchman Gilles Simon.
The 12th seed had too much claycourt experience for Simon and wrapped up the win on his first match point in 68 minutes.
The world number 16 now meets another Frenchman, Julien Benneteau, who reached the French Open quarter-finals last year.
"I felt really good from the start, which explains why the win was wrapped up quickly," Ferrer said.
German Benjamin Becker also booked his place in the second round with a 7-6, 6-2 win over Swede Thomas Johansson to set up a meeting with Czech 14th seed Tomas Berdych, who benefited from Nicolas Almagro's retirement in their first round match.
Eighth seed Briton Andy Murray pulled out of his second round match against Frenchman Marc Gicquel with a back injury. Murray's place in the draw has been taken by Spanish lucky loser Guillermo Garcia Lopez.