By Nick Mulvenney

SYDNEY (Reuters) - Venus Williams will be carrying her family flag and the hopes of the once dominant superpower of women's tennis, when the fourth seed begins her Australian Open campaign next week.

In the absence of her injured sister, defending champion Serena, Venus is the only American among the 32 women's seeds for the year's first grand slam, which starts on Monday.

Venus first played the Australian Open in 1998 when the current world number one Caroline Wozniacki was just seven years old but reached the final just once in 2003 only to be beaten by Serena.

They were, however, keeping in touch on Twitter.

"I've noticed she's taken over the house since I've left," Williams said. "Hopefully when I come back I'll recognize it, but of course I miss her and hopefully I can carry the (family) flag well."

The seven-times grand slam champion has flown in under the radar this year, not playing in any of the Australian warm-ups for the Open.

"Leading up, really just played a couple of matches, just really quiet, of course working as hard as I can to get ready for the year, you know, same old, same old," she added.

Her one public outing was in an exhibition in Hong Kong, where she lost to China's Li Na.

"I know she's just come back after injury," Li said in Sydney earlier this week. "I think she had a knee problem so it was still like, if I hit the shots wide, you could still see that she did not 100 percent trust the knee."


First up at Melbourne Park will be Italian Fed Cup winner Sara Errani but Venus said she was more concerned about her own game than the threat posed by her opponents.

"People come out and play so well and sometimes you've never even heard their name and they can play, so for me it's all about playing the ball and doing whatever it takes to get to that next round until it's all over," she added.

Her position as the only American seed is a reminder that the United States has been carried by the Williams sisters for a few years now and, while it has been quite a ride, it will not go on forever.

After 29-year-old Serena (fourth) and Venus (fifth), the next American in the world rankings is Bethanie Mattek-Sands at number 59 and there are just five others in the top 100.

One of those is 36-year-old Jill Craybas, who would hardly claim to be the future of American tennis.

Russia is the current dominant power with 15 women in the top 100, nine of whom are in the top 50.

When she finally hangs up her racket, Venus's contribution to the sartorial side of women's tennis will also be missed by many, and she promised more original dress designs for this year's Australian Open.

"There'll be more illusion, and also skin... more skin this year," she said.

(Editing by John O'Brien)