The last link is severed. An era is gone.

Steffi Graf, once unbeatable and seemingly prepared to stay that way for a long time, is just another quarterfinal loser on a Grand Slam court she once called her own.Graf's final tie to her dominating reign of women's tennis was cut at the Australian Open Tuesday by a fast-talking Czechoslovak with a revitalized game straight out of Prague by way of Aspen and Sanctuary Cove.

Jana Novotna, struggling to reach the top 10, glued herself to the net and pressured the world's top-ranked but fading women's player into mistake after mistake in a 5-7, 6-4, 8-6 victory.

The Australian - which she first won for the first of three straight times in 1988 to start her "Golden Slam" of the four majors plus the Olympic gold medal - was the last of her titles to fall, and the loss was the first she had suffered in 26 matches at the 4-year-old tennis center.

Novotna, winning for the first time in 10 career meetings with Graf and reaching a Grand Slam semi for only the second time, said she just followed the advice of Hana Mandlikova, the former U.S. and Australian Open champion who is now her coach.

In the semifinals Thursday, Novotna will play sixth-seeded Arantxa Sanchez-Vicario of Spain, who turned the tables on Gabriela Sabatini and beat the fourth-seeded U.S. Open champion 6-1, 6-3.

Sabatini has been engaged in a program to turn her baseline game into a powerful all-court attack, but it was Arantxa the aggressor under the closed roof of center court Tuesday night.

Graf, who failed to reach the quarterfinals of a Grand Slam tournament for the first time since the 1986 French Open, said she felt no added pressure in the final set as her championship hung in the balance through a string of fast-paced service breaks.

Novotna and others said that vulnerability was making Graf, No. 1 for a record 180 weeks, an increasingly easy target for the power-bashing up-and-comers of women's tennis.

"Steffi's not as good in those close matches. I don't know why," said Monica Seles, the No. 2 seed who rallied from 0-3 in the first set to beat Anke Huber of Germany 6-3, 6-1 and reach the semis against Mary Joe Fernandez of Miami. Fernandez, the No. 3 seed and runner-up to Graf here a year ago, beat fifth-seeded Katerina Maleeva of Bulgaria 6-3, 6-2.

The version on display before a prizefight-like crowd today would have been the envy of

Navratilova, the nine-time Wimbledon champion, skipped the Australian to ski in Aspen, Colo., and practice with Billie Jean King in Chicago.