Radwanska, Kerber cruise into Aussie 4th round

Fourth-seeded Agnieszka Radwanska and fifth-seeded Angelique Kerber continued to roll in third-round action at the Australian Open on Friday.

Radwanska bested Great Britain's Heather Watson, 6-3, 6-1, en route to her 12th straight victory after titles in Auckland and Sydney. The 23-year-old from Poland will next face Ana Ivanovic in the fourth round.

The 13th-seeded Ivanovic, a runner-up here in 2008, ousted another former World No. 1 and fellow Serb Jelena Jankovic in a 7-5, 6-3 decision.

Kerber, who turned 25 on Friday, was also a straight-set winner, defeating American Madison Keys, 6-2, 7-5 at Rod Laver Arena. The German, like Radwanska, has yet to lose a set in this year's first major.

Li Na earned a 6-4, 6-1 victory over 27th-seeded Sorana Cirstea to move on. The sixth seed from China lost in the 2011 Australian Open final to Kim Clijsters.

A pair of three-setters highlighted the early action Friday, as 11th-seeded Marion Bartoli was dismissed by 19th-seeded Ekaterina Makarova, 6-7 (4-7), 6-3, 6-4, in a match that lasted nearly three hours, while No. 18 Julia Goerges overcame 56 unforced errors to outlast Zheng Jie, 6-3, 1-6, 7-5.

Venus Williams is in action in the night session against second-seeded Maria Sharapova.