Four-time Miami runner-up Maria Sharapova rolled to a straight-set victory in Friday's second round, while two-time champion Victoria Azarenka aggravated a right ankle injury and was forced to pull out of the Sony Open tennis event.
The French Open champion and third-seeded Sharapova, fresh off her big title at Indian Wells, needed less than an hour to dispose of Canadian wild card Eugenie Bouchard 6-2, 6-0.
Azarenka, a former world No. 1 and reigning Australian Open champion, was scheduled to meet American wild card Madison Keys in a second-round match on Day 4 at the Sony Open, but the second-seeded Belarusian was replaced in the draw by American lucky loser Lauren Davis, who outlasted Keys 6-1, 5-7, 7-6 (9-7) to advance.
The 23-year-old star, who titled in Miami in 2009 and 2011, was also forced to pull out of a quarterfinal at the big WTA event in Indian Wells last week because of the injury.
Sixth-seeded German Angelique Kerber came from behind to beat former French Open champion Francesca Schiavone 6-7 (5-7), 6-3, 6-2, while 11th-seeded Russian Nadia Petrova eased past China's Zheng Jie 6-3, 6-1 on Friday.
Eighth-seeded Italian Sara Errani rolled past Slovak Daniela Hantuchova 6-3, 6-1, while 12th-seeded Ana Ivanovic cruised past Urszula Radwanska 6-2, 6-1.
Fourteenth-seeded Maria Kirilenko blasted American qualifier Bethanie Mattek- Sands 6-1, 6-4 to also advance to the third round, where she will take on 21st-seeded Czech Klara Zakopalova, who handled Spaniard Anabel Medina Garrigues 6-3, 7-6 (7-3).
Fifteenth-seeded Italian Roberta Vinci came back to beat American Christina McHale 6-7 (2-7), 6-1, 6-3; 20th-seeded Spaniard Carla Suarez Navarro overcame American Jamie Hampton 5-7, 7-5, 7-6 (7-3); 28th-seeded Romanian Sorana Cirstea fought back to best Silvia Soler-Espinosa 2-6, 7-5, 6-2; and 32nd-seeded Frenchwoman Alize Cornet battled back to beat Laura Robson, 5-7, 7-5, 6-1.
Former world No. 1 and 2008 Sony Open runner-up Jelena Jankovic outlasted American Victoria Duval 6-3, 7-5, while Simona Halep upended 26th-seeded Tamira Paszek 6-1, 6-7 (4-7), 7-5.
Elsewhere, 2006 Miami champ Svetlana Kuznetsova took out 18th-seeded and fellow Russian Ekaterina Makarova 6-4, 6-4 and 29th-seeded Russian Elena Vesnina vaulted past Croat Donna Vekic 6-4, 6-2.