A week after Novak Djokovic and Rafael Nadal made early exits in Madrid on an experimental blue court, both showed they remain a force on red clay Friday by reaching the Italian Open semifinals.
The top-ranked Djokovic struggled with his serve in the opening set but found his range to eliminate fifth-seeded Jo-Wilfried Tsonga 7-5, 6-1. Nadal defeated seventh-seeded Tomas Berdych 6-4, 7-5.
''In the second set I played one of the best sets on clay this year and this is encouraging for the challenges to come tomorrow and with Roland Garros,'' Djokovic said. ''I am playing and feeling better every match I play.''
Nadal was equally pleased.
''It was a big match and one of the higher quality matches this year because the level of the opponent is high and he plays with big confidence and I played under pressure all the time,'' he said. ''I hit a few fantastic shots and this kind of shot comes with confidence.''
Djokovic, the defending champion, will next play Roger Federer, the winner in Madrid who cruised to a 6-1, 6-2 victory over Italian hope Andreas Seppi. Federer has never won this tournament. Nadal's semifinal opponent is sixth-seeded David Ferrer, who beat Richard Gasquet 7-6 (4), 6-3.
Among the women, Serena Williams made the last four after Flavia Pennetta quit with an injured right wrist while trailing 4-0 in the first set. It extended Williams' winning streak to 17 matches following titles in Charleston, S.C., and Madrid, but No. 18 will not come in Rome.
Williams announced early Saturday that she was withdrawing from her semifinal against French Open champion Li Na, who eliminated No. 14 Dominika Cibulkova 6-1, 7-6 (4). Williams cited an ailing back that she wants to protect ahead of the French Open.
Defending champion Maria Sharapova beat Venus Williams 6-4, 6-3. She will play No. 12 Angelique Kerber, who defeated Wimbledon champion Petra Kvitova 7-6 (2), 1-6, 6-1.
While Djokovic has not been as dominant as he was last year - when he had a 43-match winning streak - the Serb still finds a way to win without playing his best. Serving at 5-5 in the first set, he saved a potentially decisive break point with a serve and volley. Then he took six straight points.
''I really don't compare with 2011,'' Djokovic said. ''This is a new year and I had great results so far in and I'm playing good in Rome so far. I'm increasing the level as the tournament goes on and this is important.''
Down to No. 3 in the rankings this week, Nadal broke in the opening game to take control of the first set. He recovered a break midway through the second set before pulling ahead for good. Berdych was coming off a runner-up performance at the Madrid Open. He lost to Federer, who then replaced Nadal at No. 2.
Federer had never lost to Seppi, and the 16-time Grand Slam winner took just 19 minutes to win the opening set. Seppi then pleased the partisan crowd by taking the opening game of the second. He had two break points in the next game, but Federer stormed back. The Swiss star closed the match when Seppi failed to return a serve
Pennetta called for the trainer after falling behind 3-0. Her wrist was retaped but the Italian conceded during the fifth game after 28 minutes of play.
''I felt pain during the second or third point of the opening game,'' Pennetta said. ''Something happened on the backhand. ... Then not being able to serve and attack like usual, there wasn't much else to do.''
Kvitova has an abdominal injury and needed to be bandaged again after losing the first set. That seemed to work. She stormed through the second set, easily winning the first five games.
Kerber, however, came back in the final set and took the match when Kvitova netted a ball. The victory put Kerber into her sixth semifinal of the year and into the top 10 in the rankings for the first time in her career.
