DUBAI (AFP) -- Maria Sharapova launched a vigorous attack on those who say she has never played Fed Cup for Russia because she doesn't want to.

"There are so many rumors about me which are untrue and that's one of them," she said.

"Some of them are so untrue you just have to laugh at them.

"It's quite untrue that I don't want to play for Russia. I have a Russian heart," insisted the 19-year-old who has lived for most of the past decade in Florida, with increasing gossip that she might become a naturalized American.

"I play for my country," Sharapova went on.

"When you see the draw at a tournament you see my country, Russia, next to my name.

"Unfortunately in my career I don't get as much time to spend there as I would like, but when I go that's where I feel like I belong.

"It's the way of life and the culture. I lived there for seven years, and every time I go back and hear people speaking Russian, or when I call and order room service in Russia it feels so cool it's amazing to see and hear it again. That's where I feel comfortable."

Since Anastasia Myskina, who was the heroine of the Fed Cup world team title triumph in Moscow 15 months ago, has suggested she will play less for Russia, the door has seemed opened for Sharapova to make her overdue first appearance for her country of birth.

Myskina has been one of the biggest opponents of Sharapova joining the Russian team, even apparently criticizing the way she spoke the language.

Two years ago Sharapova and her father and the Russian federation president Shamil Tarpischev, decided that as she was still growing it would be better to limit her schedule and to wait.

Now she has other reasons for limiting her schedule – fitness problems. And Sharapova, who is seeded for a semifinal with defending champion Lindsay Davenport here at the Dubai Open, would not be drawn as to whether she had solved them yet.

The former Wimbledon champion has been bothered by a shoulder and pectoral muscle strain since September, restricting her to just two tournaments this year.

"Sometimes when you have practiced well and you think you are playing well, you find that when you go out to compete that you are not; at other times you find you are riding the crest of a wave," she said.

"You can't always tell. This week I just want to go out and improve with every match. This is not a Grand Slam but I definitely want to win this tournament, but I also take it as a good practice experience as well, and want to improve a few things."