KEY BISCAYNE, Fla. -- Venus and Serena Williams, their hair beads clackity, clacking in unison, asked their father when they were going to practice yesterday, and Richard Williams, who is also their coach, stared at them in shock.

"You've got to be kidding," he said. "I'm not going to go to practice."

It might sound strange that the coach wasn't going to practice, until you realize both of his daughters are playing today in the Lipton Championships women's final.

It is a historic meeting, the first in women's professional tennis history. It is also the first in any major women's tennis history since 1884, when Maud Watson, 19, beat her older sister Lillian, 26, at the inaugural ladies' Wimbledon Championships, a competition then held for amateurs.

While the Williams family was preparing for today's Stadium Court encounter, the men's singles championship was decided yesterday. Seventh-ranked Richard Krajicek defeated unseeded and No. 74 Sebastien Grosjean, 4-6, 6-1, 6-2, 7-5. Krajicek, who has won two tournaments in less than a month, wasn't as dominant as he might have been. A queasy stomach troubled him, but his serve-and-volley game still proved too strong for Grosjean, 20, who was playing in his first final.

Krajicek earned $360,000 for the victory and will be ranked No. 4 in the world when the new ATP rankings are released tomorrow.

"I think experience helped me," Krajicek said. "I didn't feel good, but I didn't get upset about it and then I adjusted. I was picking my points well and winning this tournament was very important to me."

For the Williams sisters, it is being in the tournament finals against one another that is important. "I really, really hope it's super tennis," Venus said. "I'm going to do my best to play well and she's going to do her best to play well. When it's over, a Williams will win and we'll go home."

Adds Serena: "This final will be a great feeling for me because it won't really matter who wins or loses. It will be like we both won."

Until now, Venus, 18 and No. 6 in the world, has been the big, older sister and the big cheese, while Serena, 16, has contented herself with a slower climb toward the top of the WTA rankings. Over the past three weeks, however, things have changed.

Little Serena, ranked No. 16 coming into the Lipton, has won back-to-back tournaments and 16 straight matches that have included victories over former world No. 1 Steffi Graf and current No. 1 Martina Hingis.

And after she earned her way into today's final, Serena said she's due.

"I've always expected to win," Serena said. "I really got tired of losing in the past. Every time I looked around, I was losing, losing and losing. So now it's time to do a little more winning."

Hingis and Graf had similar thoughts on today's match: Serena is ready to win.

"I think Serena definitely has a big chance now," Hingis said. "I felt like before when they went on court [against each other], almost like Serena was -- she wasn't allowed to win at that stage. I think right now, whoever is better is going to win."

And the better player, said Graf, could very well be Serena. Graf has lost to both sisters, falling to Serena in the Indiana Wells final two weeks ago and to Venus here in the semifinals two days ago.

"Serena is really playing very well right now," Graf said. "I think she's serving a little better and returning probably a little more aggressive than Venus is and that's probably the key."

Besides meeting daily on the practice court, the sisters met twice professionally in 1998. Venus won both on the hard court in the round of 64 at the Australian Open and on the clay in the quarterfinals of the Italian Open.

"I've been working hard at this since I was 4, and there comes a time when you have to start winning, too," Serena said. "It's finally paying off and I guess you could say Venus and I are even now."

And instead of showing sisterly irritation at Serena's push to co-opt the spotlight, Venus smiles. "I've been predicting this," she said.

And, in fact, many have been predicting this -- and dreading it.

Though Venus has made it to the finals of only one Grand Slam, the 1997 U.S.. Open, and though they have won only six -- soon to be seven -- singles titles overall, Graf agreed that there is little doubt that this is the beginning of a change in women's tennis.

"Their athleticism is incredible," Graf said. "They move extremely well. They're taking risks. They go for their shots. They don't really have a certain weakness and they're trying things, like trying to get to the net. They're very tall and big. That's definitely a plus. All those things are definitely working for them."

Once they get consistent , and if they keep showing up on opposite sides of the women's draw, there is little doubt that the historic final of today could soon become the expected final of the future.

"We're planning so long, working so hard for this," said Richard Williams. "When I think about where we came from out of the ghetto to where we are right now, it makes me very nervous. You probably heard me say in the past, my girls would be No. 1, and you know I wanted them to get to this point, where they would be competing against each other in a final. But now that they are, I find I'm not ready.

"My only hope in watching my babies during this final is that I don't cry."

NOTES: Hingis and Jana Novotna rallied past Mary Joe Fernandez and Monica Seles, 0-6, 6-4, 7-6 (7-1), to win the doubles. There have been three all-brother finals on the ATP Tour: Gene Mayer defeated Sandy Mayer in 1981 in Stockholm, Sweden; Emilio Sanchez defeated Javier Sanchez in 1987 in Madrid, Spain; and John McEnroe defeated Patrick McEnroe in 1991 in Chicago. The only younger brother to win was Gene Mayer. Two-time Grand Slam winner Rod Laver, 60, conducted a clinic for children. It was first public tennis appearance since he suffered a stroke in July.

Pub Date: 3/28/99