Maria Sharapova and David Ferrer made easy progress into the quarter-finals with convincing wins on day seven at the Australian Open.
Sharapova wasted little time in the second seed by beating Kirsten Flipkens 6-1 6-0, while fourth seed Ferrer strolled past Japan’s Kei Nishikori 6-2 6-1 6-4.
Women’s fourth seed Agnieszka Radwanska easily beat Ana Ivanovic, but fifth seed Angelique Kerber crashed out to 19th seeded Ekaterina Makarova of Russia.
Ekaterina Makarova (Rus)  beat Angelique Kerber (Ger)  7-5 6-4
Moscow’s Makarova added the scalp of Kerber to her collection after knocking out Serena Williams at the same stage last year.
Germany’s Kerber was hampered by a back injury as Makarova won in an hour and 32 minutes.
“I could move; that was fine. But just my serve, when I go back, there is a lot of pain there,” said Kerber.
“I actually feel it like two, three days. So I was thinking it will be maybe not too bad, but in the first set I was feeling that and it was actually worse and worse.”
Makarova will next face compatriot Maria Sharapova and said: “I think it will be really interesting and I really want to play against her [Sharapova].”
“Last year I was so surprised [to reach the quarter-finals] a little bit and had so many thoughts on my mind. This year, I’m a little bit used to it. I think I’ll be ready to play a good game.”
David Ferrer (Spa)  beat Kei Nishikori (Jpn)  6-2 6-1 6-4
David Ferrer eased his fourth-seed into his third straight Australian Open quarter-final in two hours 10 minutes against the 16th seed.Japanese number one Nishikori had won two of their previous three matches and was a quarter-finalist in Melbourne last year, but struggled with 65 unforced errors to the clinical Ferrer’s 24.
“I started very well and when I won the first games he got down a little bit and I took my chance,” Ferrer said.
“I didn’t make any mistakes for the first two sets and to reach the quarter-final here again I am very satisfied.”