by Matt Cronin, Special to FOXSports.com

Their head-to-head matchup is locked at 10-10 and they've met four times at Wimbledon, each winning twice and Venus having taken her sister down in a brilliantly played 2008 final.

They have combined for seven out of the last nine titles and clearly, Centre Court at Wimbledon is the House of Williams and someone is going to have to steal the keys to the front door if they want to keep the family from pocketing their eighth combined title.

"Definitely (it's ours to lose)," Serena said. "I feel like if I'm not playing well, if I don't do the right things, I definitely lose it on my racket."

Serena says that she is more than aware of Venus' presence on the other side of the draw and knows just how well her older sister is playing. Last year, she was sorely disappointed after losing the final. And while she complimented her beloved sister's play, she said she blew it. Serena knows that if she's to win her first Wimbledon title since 2003, she's going to have to enter Venus' rapid orbit.

"I was hitting with her the other day," said Serena, who destroyed Daniela Hantuchova 6-3, 6-1 on Monday. "She was beating me, so I was mad. I thought I was playing really well, so I was frustrated."

Once again, Venus came into the tournament as the favorite to win the title and after four brilliantly played matches, she's looking the part. On Monday, she tore apart 2008 French Open champion Ana Ivanovic before the Serbian retired with a left thigh injury down 1-6, 1-0.

Ivanovic's retirement shouldn't take a away from Venus' sterling performance, as she battered the Serbian from the first ball, twisting in big serves, clubbing huge returns and punching crisp volleys. Venus denied the tearful Ivanovic any opportunity to get into the match and there's no denying how very much in charge she's been in every one of her matches.

"I'm a control freak," said Venus, who has only lost 15 games in four matches, "I love controlling. I'm used to that. That's how I was taught to play, so I was pleased to go out there and play well against someone as good as her."

Despite not having won a major off grass since 2001, Venus continues to play at a level far above the rest of the field, with the slight exception of Serena. She's won 31 sets in a row at Wimbledon, which goes all the way back to 2007.

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Unlike on hardcourts, where she often plays too conservatively and can be stretched out in rallies, on grass, Venus always seems to be moving forehand, especially with her returns of serve, when she goes after weak second serves with a furious vengeance.

"That tennis is rewarding on this surface," said Venus, who is 62-7 lifetime at Wimbledon. "That's how I was taught to play. Whether I do it or not, it's not because of my coaches. It's my own decision of whether I'm going to come in or stay back. But if it's in the right position for me, then I hit. If it's a little too close or a little too far, then I play more percentages. But whenever I get a swing at it, I swing."

Venus will go up against 11th seed Agnieszka Radwanska in the quarterfinals, as the Polish 20-year-old ended American teenager Melanie Oudin's dream in a 6-4, 7-5 victory. Venus owns a 3-1 record against Radwanska, including two victories this year, a difficult tussle in Miami and a blowout in Rome.

Radwanska is one of the smartest young players on the circuit, and despite not being very tall, chooses to serve and volley more than a fair amount and has soft hands. But it will take more than a deeply thought-out strategy to usurp the queen of the lawns.

"She's obviously very talented," said Venus, who is on No. 1 Dinara Safina's side of the draw. "She plays a different style game, but is very effective at it. Apparently she likes this surface. But I'll continue with my methods."

Venus Williams is in the hunt for a sixth Wimbledon title. (ADRIAN DENNIS / Getty Images)

Serena faces a much tougher task in the form of No. 8 Victoria Azarenka, who bullied her in the Miami final and on Monday, gutted out a 7-6 (5), 2-6, 6-3 victory over Russia's Nadia Petrova. Azarenka loves to fight and is extremely temperamental, which showed in her win over Petrova, when she went over to a linesperson after a second set that contained some controversial calls and lifted up her hand and shook it. She had hit the psychological bottom and then only place to go was up.

"I'm an emotional player," Azarenka said. "I just have to keep trying to calm myself down sometimes, but you never know. It's not like sitting in the living room and watching TV. You're playing in 35 Celsius, it's hot, you're playing a close match. I just need maybe not to go crazy on my emotions when I'm always pumped up."

Nonetheless, the 19-year-old doesn't fear Serena, whom she also threatened at the Australian Open before retiring with heat exhaustion.

Serena would like another crack at her sister in the Wimbledon final. (Ian Walton / Getty Images)

However, Serena loves revenge matches and will be more than happy to attempt to take her pound of flesh at Wimbledon, where she's a two-time champion. She wouldn't say that Azarenka reminds her of herself, but she can appreciate her young opponent's inner fire, because she was once the same type of no-fear teenager and still has enough hot coals burning in her belly.

"When you're playing the girls who are really young, they really want it, as bad as I still want it," said Serena, whom if she wins the match, might have to face her familiar rival, No. 4 Elena Dementieva, in the semis. "It always makes for a good fight. I think it was great when I was 19, 20. I think I'm still in a great position because I'm really young in life. I feel really young out there on the court still, so I'm excited."

Azarenka's coach, Antonio Van Grichen, has faith in his student's chances, but says that she has to keep at an even keel because Serena isn't going to give her as many opportunities as Petrova did.

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"(Azarenka) believes she can do it, but she still has to do it," he said. "The key is serving and returning and staying neutral until she gets her chances and then she's going to have to grab them. Once she gets into the rallies, she can stay with her."

Serena has won two of the last three Grand Slams (10 overall) and is itching to tie Billie Jean King's mark of 12 Grand Slam singles titles. But she knows that in order to do so, she's going to have to serve and return much more effectively than she did in Paris, when she let down against Svetlana Kuznetsova in the quarterfinals. Only a more courageous Serena can win this crown, one with just as much heart and confidence as Venus is displaying.

"I feel like I definitely need to step it up, play better, really start playing some great tennis, or go home," Serena said. "And I don't want to go home, so I feel like I'm just getting more serious."