THE possibility of an all- Williams semi-final at the Australian Open looked likely after both sisters won their fourth-round matches at the Rod Laver Arena yesterday.

Defending champion Serena ended local hopeful Sam Stosur’s campaign 6-4 6-2 after sixth seed Venus recovered from a sluggish start to overcome Francesca Schiavone 3-6 6-2 6-1.

The American sisters are now just one win apiece from meeting each other in the last four and the chances of that happening were increased when fourth seed Caroline Wozniacki was beaten by China’s Li Na 6-4 6-3.

That left the Williams sisters as the highest seeded players left in the draw.

Should they meet it would be their first meeting at Melbourne Park since Serena won the 2003 final.

Serena stunned the home fans inside the Rod Laver Arena with a powerful serving display to completely outgun 13th seed Stosur.

The Australian had won her previous meeting with Serena at Stanford last year, but could win just two points on her rival’s serve in the first set.

The American took it 6-4 and ran away with the match in the second set to win in just over an hour.

‘‘I can’t believe it. Sam beat me last time convincingly,’’ Serena said.

‘‘I think my serve was pretty good today.

‘‘I had to come out strong because when you are playing someone like Sam you have to play this good.

‘‘I especially had to do that in front of this crowd or I would have been going home.’’ Sixth seed Venus was optimistic she could claim her first Australian Open title after her comeback win over Schiavone.

Venus said: ‘‘I’m ready to go and I feel very well. I’m hitting the ball pretty good, especially against her today.’’