Top-seeded Russian Maria Sharapova reached the third round of the 600,000-dollar hardcourt tournament here Wednesday when ailing Eleni Daniilidou retired in the second set.
Sharapova, who won her first title of the season in San Diego on Sunday, had to battle to take the first set 7-6 (7/5) but was up 3-1 in the second when Greece's Daniilidou decided she couldn't continue. She said she was still feeling the effects of an illness that had prevented her from practising.
Jankovic, runner-up to Russian Elena Dementieva here last year, managed to shrug off the after-effects of a cold to defeat China's Peng Shuai 6-1, 6-1. Her compatriot Ana Ivanovic, the third seed, also advanced, defeating American Ashley Harkleroad of the United States 6-4, 6-2.
Sharapova, who like all the top eight seeds enjoyed a first-round bye, was playing for the first time since she wrapped up her 16th career title Sunday with a three-set victory over Patty Schnyder in the San Diego final. It was Sharapova's first title since winning in Linz, Austria, last October. She is hoping to keep the momentum going as she builds toward her defence of the US Open title.
In the third round she'll face Michaella Krajicek of the Netherlands, who advanced on Tuesday. Ivanovic was playing for the first time since falling in the semi-finals at Wimbledon to eventual champion Venus Williams and booked a clash with Czech Lucie Safarova, who beat Ai Sugiyama.
In other matches, Israeli Shahar Peer's struggles continued as she fell 6-1, 4-6, 7-6 (8/6) to France's Virginie Razzano. Ranked 18th in the world, Peer has failed to advance past the round of 16 in three events since Wimbledon. Up next for Razzano is India's Sania Mirza, who is having one of the best summers of any player on the tour. The 20-year-old upset No 7 Martina Hingis in the second round on Tuesday.
In the last month, she has reached the semi-finals at Cincinnati, the finals at Stanford and the quarter-finals in San Diego. Along the way, she has become the first Indian woman to crack the top 30 in the world rankings.
Defending champion Dementieva needed just 54 minutes to dismiss American wild card Madison Brengle 6-2, 6-0. She next faces fifth-seeded Daniela Hantuchova of Slovakia, 6-3, 7-6 (7/5) winner over American Jill Craybas. Fourth-seeded Russian Nadia Petrova also advanced, beating American Lilia Osterloh 7-5, 6-3.