Eight-time defending champion Rafael Nadal extended his Monte Carlo Masters winning streak to 44 matches by beating Philipp Kohlschreiber 6-2, 6-4 Thursday, while second-ranked Andy Murray was routed 6-1, 6-2 by Stanislas Wawrinka in the third round.
Top-ranked Novak Djokovic put his sore right ankle to the test again, rallying from a set down for the second straight match to beat Juan Monaco of Argentina 4-6, 6-2, 6-2.
"It was very difficult for me today," Djokovic said. "Another tough match. I am trying to take things day by day. I didn't know what to expect today and I'm really glad that I won."
Murray dropped serve five times and made a number of unforced errors. He lasted less than an hour against the 13th-seeded Wawrinka, who had won their two only previous meetings on clay.
Murray was jeered off the court.
"Just looked at the stats ... 24 unforced errors is far too many. That's a set's worth. That's where half the points went," a despondent Murray said. "I hope that's not going to be the case over the next five, six weeks. I've had tough losses on the clay before and I've come back well from them. Hopefully today will be the same."
Earlier, Nadal dispatched Kohlschreiber without facing a single break point. The Spaniard will face Bulgaria's Grigor Dimitrov in the quarterfinals.
Nadal clipped a forehand winner past Kohlschreiber to break and held at love to move up 5-3 in the second set. He served out the match, clinching victory when the German scooped a backhand into the net.
"He's playing well," Nadal said. "He's able to play very well, very aggressive, very good technique. He's (a) complete player."
Djokovic skipped with delight after the 14th-seeded Monaco sent a return long on match point. The Serb had twisted his right ankle on Davis Cup duty against the United States a little less than two weeks ago and had been doubtful to play at Monte Carlo, where he lost to Nadal in last year's final.
Djokovic had a lengthy chat with a trainer at the end of the first set and decided to keep playing. He went up a break early in the second set and held for 3-0. He'll play either fifth-seeded Juan Martin del Potro or Jarkko Nieminen in the quarterfinals.
Jo-Wilfried Tsonga also advanced with a 6-3, 6-0 win against Jurgen Melzer, breaking the Austrian player four times. Tomas Berdych again struggled with his serve and lost 6-4, 6-2 to Italian Fabio Fognini.
"It's difficult to assess my game because he was not really playing his best," Tsonga said. "But I'm happy I was able to do the job. When you play tennis, you always try for perfection."
Fognini will play seventh-seeded Richard Gasquet, who defeated Marin Cilic 7-5, 6-4.