The big names continue to surge at the Australian Open, setting up a huge second week in Melbourne.
On the men's side, the Big Four remain in position in our latest edition of the Yahoo! Sports power rankings. But behind them, the pack is bunched together and jostling for position.
Fernando Verdasco was the biggest mover, after conceding just four games for the third match in a row as he demolished Radek Stepanek.
Serena Williams has endured some shaky moments, giving confidence to women's title hopefuls Jelena Jankovic, Elena Dementieva and Dinara Safina. But Williams' draw makes her an overwhelming favorite to reach at least the semis, where Dementieva could lie in wait.
1. (1) Andy Murray: Talented Brit marches on but has a tough route to the semis. Round 4: vs. Fernando Verdasco.
2. (2) Rafael Nadal: Cranking up the power as he seeks his first Melbourne final. Round 4: vs. Fernando Gonzalez.
3. (3) Roger Federer: Smoothness and consistency are back after a difficult 2008. Round 4: vs. Tomas Berdych.
4. (4) Novak Djokovic: Reigning champ is not at his peak but is still a contender. Round 4: vs. Marcos Baghdatis.
5. (-) Fernando Verdasco: Spaniard has dropped just 12 games in three matches. Round 4: vs. Andy Murray.
6. (8) Gilles Simon: No-nonsense Frenchman is targeting big Slam breakthrough. Round 4: vs. Gael Monfils.
7. (5) Juan Martin Del Potro: Big stroke-maker is emerging as a force Down Under. Round 4: vs. Marin Cilic.
8. (6) Andy Roddick: Easiest part of the draw opens up a path toward the semis. Round 4: vs. Tommy Robredo.
1. (1) Serena Williams: Far from convincing but still the favorite in an open field. Round 4: vs. Victoria Azarenka.
2. (2) Jelena Jankovic: World No. 1 is making smooth and confident progress. Round 4: vs. Marion Bartoli.
3. (3) Elena Dementieva: May never have a better chance of winning her first Slam. Round 4: vs. Dominika Cibulkova.
4. (4) Dinara Safina: Happier now on the Melbourne surface and could challenge. Round 4: vs. Alize Cornet.
5. (-) Jelena Dokic: Comeback queen is backed by a wave of Australian support. Round 4: vs. Alisa Kleybanova.
6. (6) Vera Zvonareva: Should make the quarters but further progress is unlikely. Round 4: vs. Nadia Petrova.
7. (8) Carla Suarez Navarro: Rising star's big-match mentality makes her a threat. Round 4: vs. Anabel Medina Garrigues.
8. (-) Victoria Azarenka: Tough teenager wants to improve on her best Slam result. Round 4: vs. Serena Williams.
- Fernando Verdasco
- Serena Williams
- Elena Dementieva