Venus and Serena Williams won in contrasting fashion yesterday to set up their fourth all-sister Wimbledon final and eighth Grand Slam title match.

Two-time champion Serena saved a match point and overcame Elena Dementieva, 6-7 (4), 7-5, 8-6, in 2 hours, 49 minutes - the longest women's semifinal at Wimbledon in at least 40 years. Five-time winner Venus needed only 51 minutes to demolish top-seeded Dinara Safina, 6-1, 6-0.

"Oh, my God, this is my eighth final, and it's a dream come to true to be here again and have the opportunity to hold the plate up," Venus said.

Referring to her sister's semifinal, she said: "It was so hard before my match to watch all that drama. It was so difficult. But the hardest part is next to come, to play Serena Williams."

The sisters, with 17 Grand Slam titles between them, will face each other tomorrow. Serena is seeded second, Venus third.

One Williams or the other has won seven of the last nine championships at the All England Club. Serena beat her older sister in the 2002 and '03 finals, and Venus came out on top last year.

"All I know is a Williams is going to win," father Richard Williams said.

Venus is bidding to become the first woman since Steffi Graf in 1991-93 to win Wimbledon three years in a row.

In the previous all-Williams championship matches at majors, Serena holds a 5-2 lead. Overall, the sisters are 10-10.

"The more we play, the better it gets," Serena said.

"This is what we dreamed of when we were growing up in Compton 20-something years ago. This is what we worked for, and this is what we want. Like I wanted her to win today, and she wanted me to win today."

Said Venus: "I'm happy for her to be in the final, but I have to face her and defeat her."

The difference between the semifinals couldn't have been more striking.

Serena's match was the longest women's Wimbledon semifinal by time since 1969; records are incomplete before then. Venus' win was the most one-sided women's semifinal since Billie Jean King beat Rosie Casals by the same score in 1969. The last 6-0, 6-0 semifinal was in 1925.

After Serena's tense, drama-filled escape vs. fourth-seeded Dementieva, Venus barely broke a sweat against Safina. The Russian is ranked No. 1 and was the top seed despite never having won a Grand Slam tournament. Safina won only 20 points against the third-seeded Venus, who has been playing some of her best grass-court tennis at this tournament.