Men's round-up: David Ferrer through in five, Marin Cilic slays Leonardo Mayer

The duo, who met in the 2013 final, are the only two male Spaniards in the last 16, a rarity for the claycourt specialists who last suffered an annus horribilis in Paris in 1996 when Francisco Clavet was their only representative at the same stage.

While nine-times champion Nadal advanced with an uneventful three-set win over Russian Andrey Kuznetsov, seventh seed Ferrer needed five sets to beat Italian Simone Bolelli.

A generation shift could explain Spain's mediocre year, according to veteran Ferrer.

"Tommy Robredo, Nicolas Almagro...have been injured and the Spaniards had to play against strong opponents," the 33-year-old Ferrer told a news conference after his 6-3 1-6 5-7 6-0 6-1 triumph.

"From time to time you have five or six Spanish players. But of course we are getting older and there's a new generation coming in."

Five of the top seven Spaniards in the APT rankings are 30-plus while the best hope on the women's side at Roland Garros is Garbine Muguruza.

Ninth seed Marin Cilic continued his smooth progress with a crushing win over Argentina's Leonardo Mayer 6-3 6-2 6-4 to set up a last-16 match against Ferrer.

By making the fourth round the world number 10 has now matched his best ever performance at Roland Garros, equalling his achievements in 2009 and 2010.

Despite his underwhelming record in previous years, the Croatian hit an impressive 37 winners in a comprehensive three-set win.

Also through to the final 16 is American Jack Sock after an equally convincing 6-2 6-2 6-4 straight-sets win over Croatian Borna Coric.

The victory seals the 22-year-old's best ever performance in any of the Slams and comes after a first-round upset when he beat 10th seed Grigor Dimitrov of Bulgaria.

Continuing the theme of straight-sets wins was France's Jeremy Chardy after his 6-3 6-4 6-2 triumph over Belgium's David Goffin.

Chardy became the third Frenchman into the last 16 with his win, joining Jo-Wilfried Tsonga and Gilles Simon in round four.

Richard Gasquet could make it a quarter if he can beat South Africa's Kevin Anderson, which would really give the home fans in Paris something to shout about.

20-Richard Gasquet (France) beat 15-Kevin Anderson (South Africa) 4-6 7-6(4) 7-5 6-4

7-David Ferrer (Spain) beat Simone Bolelli (Italy) 6-3 1-6 5-7 6-0 6-1

6-Rafa Nadal (Spain) beat Andrey Kuznetsov (Russia) 6-1 6-3 6-2

Jack Sock (U.S.) beat Borna Coric (Croatia) 6-2 6-1 6-4

Jeremy Chardy (France) beat 17-David Goffin (Belgium) 6-3 6-4 6-2

1-Novak Djokovic (Serbia) beat Thanasi Kokkinakis (Australia) 6-4 6-4 6-4

9-Marin Cilic (Croatia) beat 23-Leonardo Mayer (Argentina) 6-3 6-2 6-4

3-Andy Murray (Britain) beat 29-Nick Kyrgios (Australia) 6-4 6-2 6-3