Defending champion Rafael Nadal stormed into the French Open quarter-finals on Monday as three Spaniards plus Andy Murray made it through to the last eight in the bottom half of the draw.

Nadal demolished Juan Monaco of Argentina 6-2, 6-0, 6-0 in an awesome display of claycourt tennis that must have sent shivers through his rivals for the title here.

Countrymen David Ferrer and Nicolas Almagro had earlier gone through comfortably.

Sixth-seeded Ferrer cruised past countryman Marcel Granollers 6-3, 6-2, 6-0, and 12th seed Almagro pushed aside Janko Tipsarevic of Serbia 6-4, 6-4, 6-4.

Murray then joined them with a disjointed 1-6, 6-4, 6-1, 6-2 win over Frenchman Richard Gasquet.

The Scot will play Ferrer, while Nadal will go for his 50th win at Roland Garros against Almagro.

Tsonga keeps France happy

Joining them in the last eight, in matches held over from Sunday in the opposing top half of the draw, were Frenchman Jo-Wilfried Tsonga and Juan Martin del Potro of Argentina.

Tsonga, seeking to provide a first French win in the men's singles since Yannick Noah in 1983, returned to action against Stanislas Wawrinka of Switzerland 4-2 ahead in the fifth set.

And despite dropping his serve in the opening game, he held steady to pull off a 6-4, 7-6 (8/6), 3-6, 3-6, 6-4 win that saw him into the quarter-finals at Roland Garros for the first time.

Next up will be a meeting with top seed Novak Djokovic of Serbia, who has history-making on his mind too as he bids to become the first man in 43 years to hold all four Grand Slam titles at the same time.

"It was tough yesterday as it was dark at the end. I don't know if was great for me or not," Tsonga said.

"But I came on the court this morning with a good spirit. I had a good night's sleep and I was ready to play again."

Del Potro was two sets to one up against Tomas Berdych of the Czech Republic when darkness fell on their fourth round tie late Sunday and he wasted little time on their return Monday to complete a 7-6 (8/6), 1-6, 6-3, 7-5 win.

His reward will be another crack at third seed Roger Federer, against whom he lost a thrilling five-setter in the 2009 semi-finals.

Felt sorry for Monaco: Nadal

Second seed Nadal won 17 games in succession to destroy Monaco and afterwards said he had to feel sorry for his close friend for suffering such a heavy defeat.

The Spaniard, bidding to become the first man to capture seven Roland Garros singles titles, celebrated his 26th birthday on Sunday while title rivals Djokovic and Federer were struggling into the last eight.

Monaco, the 13th seed, went into Monday's match with solid claycourt form under his belt having captured titles in Vina del Mar and Houston this year.

But he had lost all three previous clay meetings against Nadal, claiming just 10 games in the process, and the 28-year-old was swept aside again by the champion in just one hour and 46 minutes on Suzanne Lenglen court.

Murray has never beaten Ferrer on clay

Fourth seed Murray looked all at sea for a set and a half before his fourth round clash with Gasquet turned dramatically late in the second set as the Scot found his touch and Gasquet totally lost his.

The win means that Murray has reached a Grand Slam quarter-final for the sixth straight time, with Ferrer, who he has never beaten on clay, waiting for him as his opponent.

For Gasquet there was the disappointment of failing to join countryman Tsonga in the last eight. The last time two Frenchman made the quarter-finals at Roland Garros was in 1990.

"He started very, very well, went for his shots, high risk and was playing unbelievable," Murray said of his opponent.

"I was lucky to turn it around at the end of the second set and then I started to play a lot better."