BRISBANE, Australia (AP) U.S. captain Mary Joe Fernandez says the Fed Cup format may have to change if the world's best players are to find time in their schedules to take part more consistently in the international women's tennis competition.

The United States will be without its top three singles players, Serena and Venus Williams and Sloane Stephens, when it faces Australia in a World Group playoff this weekend.

The Americans still have a strong team for the match, which will be played on a temporary clay court at Brisbane's Pat Rafter Arena. The lineup includes No. 22-ranked Madison Keys, Coco Vandeweghe (36), Christina McHale (57) and Bethanie Mattek-Sands (89).

The absence of the biggest names raised questions over whether the tournament can retain its prestige.

Fernandez told a news conference Wednesday the format and scheduling of the tournament made it difficult for top players such as the Williams sisters to easily commit. She said players mapped out their schedules at the start of the year and were then required to find space at late notice for Fed Cup ties.

''We didn't find out we were coming to Australia until the second week of February,'' Fernandez said. ''It's not the most convenient thing to do, come to Australia when everyone's heading to Europe or in the States.''

Fernandez said she'd spoken to the International Tennis Federation about revising the format, and agrees a format more like the men's Davis Cup could make it ''a little bit easier to follow and it will be a lot more convenient for the players.''

Australia captain Alicia Molik said the attitude to Fed Cup differed from nation to nation but few countries took the tournament more seriously than Australia, which will be represented on the weekend by Sam Stosur, Daria Gavrilova, Casey Dellacqua and Arina Rodionova.

''The tradition starts young,'' Molik said. ''We're fortunate in Australia to have our best players wanting to play and put their hand up at all times to represent their country.''

Molik said she understood the reasons the top U.S. players were absent and said Australia would not be taking their opponents lightly.

''In Serena and Venus's case, Olympics is a big goal for them, they have (already) qualified,'' Molik said. ''The U.S. has the luxury, they have a lot of top players, but I think it just really points out that we here in Australia have players who are really commited to our country.''