Can Maria Sharapova restore order?

WIMBLEDON, England -- Maria Sharapova, still just 24, finds herself the defender of the old order at Wimbledon. The absence of Kim Clijsters, the exits of the Williams sisters in the fourth round Monday and earlier craziness have left her the only Grand Slam champion still in the draw.

The first of her three major titles came here as a 17-year-old in 2004, but a long slump caused by shoulder problems means she has not been to the semifinals since 2006. That is likely to change Tuesday. After an unusually good clay-court season, the Russian is once again playing up to her past credentials and, fiance in tow, looks focused and happy.

After she won her fourth-round match, a television interviewer asked Sharapova what has stayed the same and changed since 2004. "I was tall back then; I'm still tall," she joked.

More earnestly, she continued, "I was inexperienced then. Now I have a lot of years of experience, a lot of ups and downs, and here I still am."

Meanwhile, a group of younger 20-somethings are trying to announce their arrival. Victoria Azarenka, 22, and Petra Kvitova, 21, have established themselves as potential Slam threats and are looking to take another step forward. Azarenka will be trying to make her first Grand Slam semifinal, and Kvitova will be trying to better her surprise run to the semifinals last year. Two former up-and-comers, Sabine Lisicki and Tamira Paszek, are re-establishing themselves after injury problems.

Dominika Cibulkova is also in the mix after derailing the expected quarterfinal faceoff between Caroline Wozniacki and Sharapova, and so is Tsvetana Pironkova, who knocked out Venus Williams.

At 26, Marion Bartoli is the oldest in the draw, reversing a recent trend of veterans dominating the majors. She held off a battling Serena Williams to defeat the defending champion on her fourth match point in the fourth round.

With the sisters out, this year will be the first time since 2006 that neither will hoist the trophy. Some see it as validation for the rest of the field, which did not allow the rusty Williamses to win in what was just their second tournament back from long injury layoffs. Some, naturally, don't. "I'm super happy that I lost," Serena said sarcastically. "Go, women's tennis."

Those who did make it through certainly earned it -- all beat the expected quarterfinalists to come through and take their spots. Here's how the matchups look.

Maria Sharapova versus Dominika Cibulkova
Theme: Tall versus small
Head-to-head: 2-2
Stat to note: 11-inch height difference

There's almost a foot separating the rangy, 6-foot-2 Sharapova and 5-foot-3 rocket Cibulkova, and the gap between their careers is almost as wide. Sharapova has won three Grand Slams, including this event as a 17-year-old in 2004, while Cibulkova will be playing in just her third Grand Sam quarterfinal Tuesday. The thing they do have in common is that neither will sit back and wait for the other to take charge.

It's well known that Sharapova likes to dictate, while Cibulkova is coached by Zeljko Krajan, who used to encourage all-out aggression on every shot from former pupil Dinara Safina and is doing the same with his latest project. It's a little odd, given Cibulkova's size and skills, but it's been working for her this week. She clocked 31 forehand winners in taking down world No. 1 Caroline Wozniacki in the previous round, including match point. Sharapova still will have the edge in power, just as Cibulkova still will have the edge in speed despite Sharapova's improved movement. But it might be the edge in experience that counts most.

Prediction: Sharapova

Sabine Lisicki versus Marion Bartoli
Theme: Grass class
Head-to-head: 2-1 Lisicki
Stat to note: 124 mph -- Lisicki's fastest serve of the tournament

Lisicki, one of the feel-good stories of the tournament, is topping the serve speed leaders among the women and is among only a handful of women on tour who can count the serve as a major weapon. That gives her a big edge, especially on this surface, as she showed by reaching the quarterfinals here two years ago as a 19-year-old. Between then and now, she was beset by ankle problems and seen most often being wheeled off or carried off the court at Grand Slams. The latest episode was at the French Open, but that was due to cramping rather than injury.

The incident was attributed to gluten problems, and like Novak Djokovic, Lisicki has been on a tear since going gluten-free. She won the grass-court warm-up in Birmingham and upset French Open champ Li Na in a big Centre Court battle in the second round. Tears of joy followed. "I knew I'm going to get back," the German said. "I was very disciplined and really wanted to get back, so I was never in doubt."

Former finalist Bartoli is on a nice run of her own -- 18-2 in her past four events, and counting. That included a run to the semifinals of her home event at the French Open and nine straight wins on grass so far. She has had a lot of small injuries this year but has bounced back strongly each time. Feeling ill with stomach problems in her third-round match, she sent her parents off the court and somehow battled to win 9-7 in the third and came back this week to take out Serena Williams in straight sets. With all her pre-serve routines and two-handed shots off both sides, Bartoli is a quirky sight but extremely effective with Monica Seles-like angles.

Looking as fit as she can, the Frenchwoman served well at key moments against Serena and scrambled well, all of which should stand her in good stead against Lisicki. The question is how much emotional and physical energy she has left after a draining six weeks.

Prediction: Bartoli

Tamira Paszek versus Victoria Azarenka
Theme: Overdue
Head-to-head: 1-0 Azarenka
Stat to note: 75 -- ranking differential

These two were juniors rivals but have taken different paths in the past few years. Azarenka has risen steadily and looks ready to make her first major impact in a Grand Slam. It might have come before, if only she could finish matches -- there was that retirement up a set against Serena Williams at the Australian Open in 2009, fainting on court at the U.S. Open last year and three mid-match stoppages so far this year. Mentally, however, the once-hotheaded Azarenka has gone up a level since March, rarely losing to players she shouldn't (except through retirement) and showing a new maturity in her approach to matches.

She has gone through a tough group of ovas to get to this stage -- grass-suited Magdalena Rybarikova, Iveta Benesova, a resurgent Daniela Hantuchova and the tough, if unpredictable, Nadia Petrova. With Venus Williams gone, she might be the favorite to get to the final. Not that anyone seems to be noticing. Azarenka, alone among the top players, has reached the quarterfinals without being called for a single news conference.

Paszek, meanwhile, was one of the tour's top prospects three or four years ago and is from Austria, with Chilean, Tanzanian and Kenyan connections from her parents (cosmopolitan even for tennis standards). Since rising to No. 35 as a 17-year-old, however, she has struggled. There was a difficult and ultimately fruitless search for a coach to replace Larri Passos, the former coach of Gustavo Kuerten. Then came a back injury in 2009, along with a brief controversy about whether the treatment she received for the problem might have violated anti-doping rules (after a hearing, the federation did not impose a penalty). Now, she's back to working with her dad and feels like the troubles are behind her. "Definitely," she said in an interview after her fourth-round win. "I've always known one day I was going to make it back. My mind was there."

Paszek defeated Francesca Schiavone in a 3-hour,19-minute marathon in the third round before another three-set win in the fourth round. "Another amazing player," she said of Azarenka. "I've known her for a long time. [I'll] try to enjoy, want to keep going." Unlike many in her age group, Paszek has some flair in her game, but she is likely to struggle against Azarenka's sheer force off the ground. The focused Azarenka is eyeing her first Grand Slam semifinal -- and perhaps beyond.

Prediction: Azarenka

Petra Kvitova versus Tsvetana Pironkova
Theme: Dark horse repeats
Head-to-head: 2-0 Kvitova
Stat to note: Previous Wimbledon result -- semifinals

Last year's surprise semifinalists face off in the quarterfinals, so only one of them will make it that far this year. The powerful Kvitova has built on her run last year, but the more nuanced Pironkova has not. What Pironkova has done, however, is maintain her voodoo over Venus Williams, scoring her third straight win against the seven-time Grand Slam champ.

"When I come there, I just feel so relaxed. I really like the atmosphere," Pironkova said of her Wimbledon resurgence. "I really do like the grass."

With her ability to keep points going and a unusual slice forehand, the Bulgarian will give Kvitova something to deal with, but the Czech has a real chance to go a step further than last year and reach the final.

Prediction: Kvitova

Kamakshi Tandon is a freelance tennis writer for ESPN.com.