ROME (Reuters) - Rafa Nadal produced an "almost perfect" display to beat John Isner and book his spot in the quarter-finals of the Italian Open on Thursday as Roger Federer overcame a brief lapse before easing past Kevin Anderson.
Fourth seed Nadal, who has struggled to find his best form this season in the wake of the wrist injury and appendicitis issues that undermined him last year, was imperious against the big-serving American and closed out the match 6-4 6-4.
He did not face a single break point and won 90 percent of his first-service points.
"I was almost perfect," Nadal told Sky Sports Italia. "It was a good match, I'm satisfied."
The Spaniard, who fell to seventh in the rankings after Sunday's Madrid final defeat to Andy Murray, looked to be back on the path to discovering his best claycourt form.
The warm weather made the court faster and Nadal's top-spin forehand forced Isner on the defensive, something the statuesque American does not do well.
Nadal, a seven-time champion in Rome, will now face Stanislas Wawrinka, who beat Dominic Thiem 7-6(3) 6-4 to record consecutive victories for the first time since February.
Second seed Federer appeared to be heading for an easy win against Anderson as he broke early in both sets and held two match points on serve, leading 5-2 in the second set.
Anderson valiantly fought back to level, however, before losing the last two games and the match 6-3 7-5.
The Swiss will now play the winner of Tomas Berdych's clash with Fabio Fognini.
Seventh seed David Ferrer crushed fellow Spaniard Guillermo Garcia-Lopez 6-1 6-3 and will play Belgian David Goffin who reached the last eight after Andy Murray withdrew with fatigue.
In the women's event, Maria Sharapova came back from a 3-1 first-set deficit to beat Bojana Jovanovski 6-3 6-3.
The Russian, a twice winner in Rome in 2011 and 2012, has taken up the favourite's mantle after Serena Williams withdrew due to a right elbow injury.
Fourth seed Petra Kvitova proved too powerful for former world number one Jelena Jankovic, hitting 23 winners, with only 19 unforced errors.
Second seed Simona Halep easily downed Venus Williams 6-2 6-1 in just over an hour while Eugenie Bouchard double faulted on match point, before losing a three-hour battle to Carla Suarez Navarro 6-7(2) 7-5 7-6(7).
(Reporting Jacopo Lo Monaco; Editing by Toby Davis)