ranked Novak Djokovic and No. 3 Roger Federer each needed three sets to reach the quarterfinals of the BNP Paribas Open Wednesday, while No. 1 Victoria Azarenka improved to 21-0 on the season with a straight-set win on the women's side. Second-ranked Rafael Nadal beat 21st-seeded Alexandr Dolgopolov of Ukraine 6-3, 6-2 to set up a quarterfinal against David Nalbandian, who upset sixth-seeded Jo-Wilfried Tsonga 3-6, 7-5, 6-3. Djokovic, the two-time defending champion, beat Pablo Andujar 6-0, 6-7 (5), 6-2. Federer got by Thomaz Bellucci of Brazil, 3-6, 6-3, 6-4 in a fourth-round match that finished under the lights and completed a parade of the world's highest-ranked players. It was Federer's 12th straight win, making him 19-2 on the year. It was also his 74th consecutive victory against a player outside the top 20, and he has won 36 of 38 matches since the US Open. Federer will next play ninth seed Juan Martin del Potro of Argentina who overcame Uzbekistan's Denis Istomin 7-6, 6-7, 6-2. “I struggled early on making the transition from day to night,” said Federer. Azarenka routed fifth-seeded Agnieszka Radwanska 6-0, 6-2 in just over an hour to tie Serena Williams' 2003 record of 21-0 to start a season. The Belarusian has already won three titles this year, and now has her sights on Martina Hingis' record 37-0 start to the 1997 season. “I was executing my shots brilliantly,” said Azarenka, who next plays 18th-seeded Angelique Kerber of Germany, a 6-4, 6-2 upset winner over No. 8 Li Na. Radwanska won two of the final three games in the quarterfinal match to avoid a shutout in falling to 1-5 in her career against a No. 1-ranked player. Other winners were: No. 11 seed John Isner, who defeated Australia's Matthew Ebden 6-4, 7-5; and No. 12 Nicolas Almagro, who defeated No. 7 Tomas Berdych 6-4, 6-0. No. 13 Gilles Simon outlasted young American Ryan Harrison 7-5, 5-7, 6-1 to set up a quarterfinal against Isner.
