Williams sisters crowned doubles champions at Australian Open

Defending champions Venus and Serena Williams have won their fourth Australian Open women's doubles title, beating Cara Black and Liezel Huber 6-4, 6-3 at Rod Laver Arena on Friday, maintaining the partnership's perfect record in grand slam finals.

The Williams sisters won the Australian title for the first time in 2001 and added championships in 2003 and last year. Black, of Zimbabwe, and Huber, a South African-born American citizen, won the Australian Open doubles title in 2007 and were the top-seeded team in the tournament this year.

The Williams sisters have now beaten the top-ranked pair in all three of their meetings, including the US Open final last year.

Serena will clash with Justine Henin for the women's singles title on Saturday.

Top seeded Leander Paes and partner Cara Black are playing against rivals seventh seeded Liza Raymond and Wesley Moody in the semi final of mixed doubles.