JOIN USNadal cruises into quarters
The Spanish top seed, who won a seventh straight Monte Carlo Masters crown on his favoured clay surface on Sunday, is bidding for a sixth title in the Catalan capital in seven years.
He took his winning record on the red dust since 2005 to 183-6 to set up a clash with Frenchman Gael Monfils, who beat compatriot and ninth seed Richard Gasquet 6-4, 7-6.
Fourth-seeded Spaniard David Ferrer, beaten by Nadal in the Monte Carlo final, eased through to the last eight with a 6-3, 6-2 success against Victor Hanescu of Romania.
Ferrer will next meet Austrian Juergen Melzer, the sixth seed, who had to come from a set down to get past 11th seed Albert Montanes, another Spaniard, 6-7, 6-3, 6-2.
Stosur in semis
Australian Samantha Stosur, last year's French Open finalist, edged past world number three Vera Zvonareva 2-6, 6-3, 7-6 to reach the Stuttgart Grand Prix semifinals on Thursday.
Stosur, who skipped the Fed Cup play-off against Ukraine at the weekend to focus on her claycourt preparation, saw her work pay off as she fought back from a set down to beat the Russian, who broke a staggering nine strings and briefly played with her coach's racquet.
Stosur will now face 22-year-old Julia Goerges, ranked 32nd, who beat fellow German Sabine Lisicki 6-4, 6-4.
An opening game lasting 14 minutes set the tone for a tight encounter with second-seed Zvonareva breaking her opponent on her ninth opportunity.
The Russian held serve comfortably and got another break when the Australian whipped a crosscourt forehand wide to go 4-1 up before taking the first set 6-2. Stosur initially looked uncomfortable on Stuttgart's indoor red clay in an error-strewn first set performance.
The 27-year-old battled her way back into the contest, serving with much more kick and hitting a better forehand to lead 5-3 and grab the second set when Zvonareva fired a service return long.
The pair traded blows in the third set before Stosur played a near flawless tiebreak to clinch the match on her first match point when Zvonareva's return flew long.