Maria Sharapova and Venus Williams have both been ruled out of next month's Fed Cup World Group fixtures.
Sharapova, who crushed Williams in straight sets in the third round of the Australian Open, has been left out of the Russia team for their tie against Japan.
The world No 2 has a busy WTA schedule in the United States, and Russia captain Shamil Tarpishchev said: "I think it would be unwise to call her as she's unable to perform top-class tennis on both fronts."
Tarpishchev has also omitted Australian Open quarter-finalist Svetlana Kuznetsova and selected Maria Kirilenko and Ekaterina Makarova.
Williams has withdrawn from next week's Open GDF Suez tournament and also made herself unavailable for the USA's FedCup clash with Italy.
The world No 26 struggled with a back injury in Melbourne and has been advised to rest.
She said: "Unfortunately I have a pain in my back which obliges me to rest and so to miss the Parisian event as well as the Fed Cup the week after."