Serena reaches Wimbledon 4th round

LONDON - Serena Williams cruised effortlessly into the Wimbledon fourth round on Saturday as the first week's shockwaves left just eight of the top 20 seeds still standing.

Women's defending champion Serena Williams was equally ruthless taking just over an hour to carve out a 6-2, 6-0 win over Japanese 42-year-old Kimiko Date-Krumm.

It was the 600th win of Williams's career as the American continued her gentle cruise towards a sixth Wimbledon title and 17th Grand Slam crown.

She will face German 23rd seed Sabine Lisicki for a quarterfinal place where victory will also give her a 35th successive win, taking her level with sister Venus's record set in 2000.

"Wow, 600 wins. I had no idea. What better place than under the roof at Centre Court to achieve it," said the 31-year-old American.

Only four of the top 10 men's seeds and four of the top 10 in the women's draw have made it to the second week after the Grand Slam heavyweights of Roger Federer, Rafael Nadal, Maria Sharapova and Victoria Azarenka had all exited by Wednesday.

Laura Robson took full advantage by becoming the first British woman to make the last 16 for 15 years when she came from a set and 3-5 down to defeat New Zealand's Marina Erakovic, 1-6, 7-5, 6-3.

The 19-year-old goes on to face Kaia Kanepi of Estonia, a former quarterfinalist.

Robson, currently ranked 38 in the world, will also move into the top 30 after the tournament, the first British woman to break that barrier since Jo Durie in April, 1987.

Polish fourth seed Agnieszka Radwanska, the runner-up to Williams last year, defeated Madison Keys of the United States, 7-5, 4-6, 6-3

She will face 2010 semifinalist, Tsvetana Pironkova of Bulgaria who defeated Petra Martic of Croatia, 6-1, 4-6, 6-2.

Chinese sixth seed Li Na survived a roller-coaster of a battle to edge Czech veteran Klara Zakopalova, 4-6, 6-0, 8-6.

Next up for Li is Italian 11th seed Roberta Vinci who saw off Slovakia's Dominika Cibulkova, 6-1, 6-4.

The 2011 champion Petra Kvitova, the eighth seed and highest ranked player in her half after the exits of Sharapova and Azarenka, reached the fourth round with a 6-3, 2-6, 6-3 defeat of Russian 25th seed Ekaterina Makarova. - Agencies