time champion Jelena Jankovic rolled to a surprisingly easy 6-0, 6-1 win over Venus Williams Thursday and prevented an all-Williams semifinal at the Italian Open. Venus struggled with her serve and never really threatened on a cool evening at the Foro Italico. Earlier, younger sister Serena Williams overcame a rough stretch in the second set to dispatch Maria Kirilenko 6-1, 6-4. In the other half of the draw, former No. 1 Ana Ivanovic beat 14th-seeded Nadia Petrova 6-2, 7-5 and will face 26th-ranked Maria Jose Martinez Sanchez of Spain, who beat Lucie Safarova of the Czech Republic 7-6 (6), 6-4. Venus was returning from a month out due to right knee tendinitis and committed 11 unforced errors to Jankovic's one in the first set alone. Jankovic won this clay-court warmup for the French Open in 2007 and 2008. She entered with a 5-5 career record against Venus and was not expecting such an easy match. Cilic rallies to advance In Munich, top-seeded Marin Cilic of Croatia rallied to overcome Simon Greul of Germany 6-7 (6), 6-2, 7-5 and advance to the quarterfinals of the BMW Open Thursday. Cilic's double-fault in the tiebreaker gave Greul a set point and the German hit a forehand winner. Cilic fell behind 4-2 in the third, but rallied again and broke serve for a decisive 6-5 lead. After rain delayed the start of play for four hours, fourth-seeded Philipp Kohlschreiber of Germany dismissed Santiago Ventura of Spain 6-2, 6-1, No. 5 Marcos Baghdatis defeated Marco Chiudinelli of Switzerland 6-3, 6-4, and No. 6 Nicolas Almagro of Spain beat Kevin Anderson of South Africa 6-2, 5-7, 7-6 (5). Seeds fall away In Portugal, a relaxed Roger Federer spent time polishing his clay-court game on the practise court as potential rivals fell away through injury or illness at the Estoril Open here Thursday. The world No. 1 whose French Open title defense starts in just over a fortnight, put in a training session at the Estadio Nacionale, where he is bidding for a second title after 2008. Federer plays veteran Frenchman Arnaud Clement in Friday's quarterfinals and holds a 6-3 advantage in that series with their last meeting in 2006. While Federer was keeping fit, there was bad news for organisers as ailing French third seed Gael Monfils joined injured number two Croatian Ivan Ljubicic in making a late pullout. Monfils, ranked 18th but without an ATP start for six weeks due to a hand injury, was unable to play his opening second-round match after being ill throughout the night. “I barely slept an hour last night,” Monfils said after pulling out against Spain's Alberto Martin, who later beat compatriot David Marrero 6-1, 6-2. On court in the second round, Spanish fifth seed Guillermo Garcia-Lopez put out one of three Portuguese players remaining as he beat Leonardo Tavares 6-2, 6-2. Portugal guaranteed itself a player in the final four for the first time here as Rui Machado beat Michal Przysienzy 6-4, 6-4 and Frederico Gil defeated Santiago Giraldo by a similar scoreline. In the women's WTA draw, second seed Sorana Cirstea of Romania reached the semifinals with win over Arantxa Rus of the Netherlands 6-4, 6-1, while Chinese seventh seed Peng Shuai continued her impressive Estoril debut as she upset fourth seed Anabel Medina Garrigues of Spain 4-6, 6-4, 6-3. Djokovic in quarters In Serbia, defending champion Novak Djokovic advanced to the quarterfinals of his hometown tournament Thursday by beating Fabio Fognini of Italy 6-4, 6-4 in the second round of the Serbia Open. Second-seeded John Isner of the US made it to his first quarterfinal since February by easily defeating Josselin Ouanna of France, while Richard Gasquet of France ousted eighth-seeded Andreas Seppi of Italy 4-6, 6-2, 7-5. Serbian 18-year-old wild card Filip Krajinovic rallied to beat Horacio Zeballos of Argentina 6-3, 1-6, 7-6 (5) for his first ATP Tour quarterfinal. The Serbia Open is organized by the Djokovic family.