WIMBLEDON, England — A spot in her seventh Wimbledon final already secured, Venus Williams headed back to Centre Court to catch the end of the next match.

Scouting? Not really. More like rooting. And when Thursday's second semifinal ended, Williams stood, smiling and applauding for the woman who won, the woman she will have to beat to earn a fifth championship at the All England Club: her younger sister, Serena.

The most unusual and, at times, uncomfortable rivalry in tennis is once more in the spotlight at the pinnacle of the sport: Venus will play Serena in their third all-in-the-family Wimbledon final Saturday.

It's their seventh Grand Slam title match — Serena holds a 5-1 edge over her sister — but first final at any tournament since 2003.

"Our main focus is obviously both of us getting to the final," Venus said. "Then, from there, it's every Williams for themself."

While there are, of course, differences in personality (Venus calls herself a nerd; Serena is more extroverted) and game (Venus' serve is faster, for example, and Serena's return is considered better), the siblings' paths to what will be their 16th head-to-head matchup were remarkably similar.

Neither has lost a set in the tournament, and Venus won her semifinal over fifth-seeded Elena Dementieva of Russia 6-1, 7-6 (3), before Serena hit 14 aces in a 6-2, 7-6 (5) victory over 133rd-ranked Zheng Jie of China. Coincidentally, each Williams won 80 of the 141 points in her match.

How unsurprising were Thursday's results? Consider this: The sisters are now a combined 100-13 at Wimbledon for their careers; Dementieva and Zheng are a combined 29-13.

"We've both been working extremely hard," said Serena, who holds an 8-7 career edge over Venus. "It's just coming together."

Both have been ranked No. 1, but a combination of injuries and inactivity contributed to Venus being No. 7 now, and Serena No. 6. All of the top four-seeded women were gone by the quarterfinals, the first time that's ever happened at Wimbledon, which cleared the way a bit for the sisters.

Then again, they way they've been playing over these two weeks, and the way they always seem to play on grass, who's to say it would have made a difference?

Back on May 30, when the city was Paris and the surface clay, first Serena, then Venus, lost in the third round at the French Open.

A little more than a month later, defending champion Venus, 28, will be going for her fifth title at Wimbledon, and seventh major overall; Serena, 26, will be going for her third title at Wimbledon, and ninth major overall.

They've combined for 11 finals appearances since 2000 at the grass-court Grand Slam tournament, including when Serena beat Venus for the 2002 and 2003 titles.

"They're both going to show up, and they both want it," said David Witt, Venus' hitting partner, who also has worked with Serena. "So it's special."

One interested party who won't be there Saturday: Richard Williams, the architect of the greatest one-family dynasty in tennis history.

The father and coach who decided to teach his daughters how to swing rackets in Compton and has seen them grace the game's greatest stages, hates seeing them slug it out against each other. So he's flying home to the United States. Won't even follow the match on TV.

"I can't stand to watch them play," he said between puffs of a victory cigarillo once the semifinals were over. "I can never do that. It makes me nervous."

It's not hard to fathom how tough it must be to try to beat your sibling, and the all-Williams matchups haven't always brought out their best play.

The men take center stage today as No. 1 Roger Federer plays Marat Safin in one semifinal today, and No. 2 Rafael Nadal meets Rainer Schuettler — who needed two days to finish his five-set quarterfinal victory over Arnaud Clement — in the other.

Federer hasn't been broken once through five matches at this year's tournament.

"I feel so comfortable on this Centre Court that my confidence level is obviously very high," Federer said after beating Mario Ancic. During this tournament, the 12-time Grand Slam champion has stretched his grass-court winning streak to 64 matches and his Wimbledon streak to 39.