The sporting world's most intriguing sibling rivalry will be revived this weekend after Venus and Serena Williams surged into the All England Club final on Thursday.

Champion Venus was the first to book her final date by bullying Elena Dementieva into a 6-1 7-6 submission while Serena survived two rain disruptions and some plucky play from new Wimbledon darling Zheng Jie before she carved out a 6-2 7-6 win.

Russian Dementieva and China's Zheng valiantly tried to gatecrash the Williams party on Centre Court but in the end wilted under a barrage of fierce thunderbolts.

Fifth seed Dementieva started as underdog despite being the highest ranked survivor in the women's draw.

It did not take long to see why. Venus blew the Russian off court in the opening set as her flaky serve started to crumble.

In fact, the glaring sun beating down on court was turning out to be more of an obstacle for Venus who squinted as she smashed away an overhead to seal the first set.

A muttering and squealing Dementieva provided more entertainment and stiffer resistance in the second but it all amounted to nothing when she surrendered her title hopes by scooping a forehand into the net to lose the tiebreak 7-3.

VENUS MESSAGE

As soon as a beaming Venus skipped off court, the seventh seed had a message for her sister.

"I'm dying for S Williams to get through," said Venus, who is chasing a fifth title at the citadel of grasscourt tennis.

"This is my seventh final here and I'm looking forward to playing Serena in our third final and I'm rooting her on."

Serena appeared to have heeded her sister's call when she began her contest against Zheng, the first Chinese player to reach the semis of a grand slam, by blasting serves down and pounding groundstrokes into the corners.

Jus as it looked like the sixth seed would flatten her opponent, Serena's customised white rain coat came in handy when a short shower burst sent the players scurrying into the locker room with the American leading 5-2 in the opening set.

On resumption, Zheng, the first wildcard to reach the women's semi-finals at Wimbledon, was again left to dodge the missiles as Serena quickly pocketed the first set.

But Serena soon realised exactly how Zheng had managed to trample over four seeds over the past fortnight, including world number one Ana Ivanovic, despite her diminutive appearance or her ranking of 133rd in the world.

Seeming to play almost on tip-toes to make up for her 11-cm height handicap, the 1.64-metre tall Zheng moved Serena about the court with her rasping drives and two-fisted backhands.

She broke Serena for a 4-2 lead but immediately relinquished the advantage and her resolve finally folded when she produced a double fault to lose the tiebreak 7-5.

While tennis fans around world will be fascinated to see which of the two Williams sisters, who have won six Wimbledon titles between them since the turn of the century, comes out on top, there will be one person conspicuous by his absence.

ABSENT FATHER

Richard Williams was hotfooting it to the airport on Thursday to catch an early flight back to the United States because he did not want to see his "kids fight each other".

Since the top four seeds were hurled out of the tournament before the quarter-finals, Venus and Serena have been the overwhelming favourites to reach the final.

But matches between Venus and Serena are captivating, highly charged yet often disappointing affairs.

The American siblings will meet in a grand slam showpiece for the seventh time although the last time they clashed in a major final was at Wimbledon five years ago -- when Serena won a subdued battle against an unfit Venus.

When asked if there is any family discussion to decide in advance the outcome of a match between the sisters, Venus visibly bristled and said: "I find the question pretty offensive because I'm extremely professional in everything that I do on and off the court.

"I contribute my best in my sport, and I also have a ton of respect for...my family. So any mention of that is extremely disrespectful for who I am, what I stand for, and my family."

Venus will be gunning for revenge on Saturday because after trumping Serena at the 2001 U.S. Open, she has lost the five finals since. Serena leads their overall head-to-heads 8-7.