By Simon Cambers NEW HAVEN, Connecticut (Reuters) - From Chris Evert and Martina Navratilova to Monica Seles, Lindsay Davenport and the Williams sisters, the United States has dominated women's tennis for more than 30 years. But while the women's game has never been in better shape, the U.S. is in a rut.

For the first time since the inception of computer rankings in 1975, the U.S. did not have a player inside the world's top 10 when the latest list was released on Monday. Only 15 women have topped the world rankings in those 31 years and eight of them were Americans. But with Davenport in the twilight of her career, Serena and Venus Williams beset by injury problems, and Jennifer Capriati and Monica Seles all but retired, it is all change at the top.

"I honestly don't know what the answer is," Davenport, the most recent American world number one, said this week as she warmed up for the U.S. Open in New Haven. "I think Serena, Venus and I have done a pretty good job for the last decade, staying at the top. But it is unfortunate that there haven't been bigger American stars coming up to help with the load yet."

The problem, it seems, is not just a dearth of American women coming through but also a wave of top players, mostly from Russia, making life more difficult. In Monday's list, there were four Russians in the top 10.

AMERICAN IDOLS

Elena Dementieva, the world number five, said the pressure of emulating the likes of Davenport and the Williams sisters could be a factor.

"I think for American young players it is very difficult because they have so many idols," she said. "It is so hard to play to the same level as the super players, like Andre Agassi and Lindsay Davenport, and to find yourself not as perfect as they are."

"It is strange because when I play here in the United States I see all these tennis clubs and tennis academies and it's just amazing how professional they are. In Russia, it is all on the parents' support."

Compared to many countries, things probably do not look too bad. After all, the U.S. has 12 players in the top 100. Andy Roddick, the former men's world number one who returned to the top 10 on Monday after winning the Cincinnati Masters Series event, said expectations were too high.

"It's amusing to me that other countries go, you know -- they're throwing 25th anniversaries for when (Yannick) Noah won the French Open -- we go three years without and all of a sudden everybody's going crazy.

"I realise that that's because we've been spoiled in the best possible way with champion after champion after champion, but there was a similar kind of phase-in, phase-out from 1986 to 1988. People just have to understand it goes in waves."