MELBOURNE, Australia -- The Australian Open will produce not just a women's Grand Slam champion but also a different No. 1.
The current holder of the top spot, Jelena Jankovic, needed to reach the final to guarantee she would retain her lofty perch after the tournament. But her fourth-round loss left the door ajar, and those right behind have taken full advantage.
World No. 2 Serena Williams, No. 3 Dinara Safina and No. 4 Elena Dementieva have all booked spots in the semifinals, guaranteeing that whoever does best will end the tournament ranked No. 1 on the Sony Ericsson WTA Tour.
Williams and Dementieva will face each other in one semifinal, while Safina takes on Vera Zvonareva in the other.
Any of the first three will become No. 1 if she wins the title. If long shot Zvonareva ends up as champion, the winner of the semifinal between Williams and Dementieva will be No. 1.
The double prize on offer only increases the incentive for Dementieva and Safina, since neither has won a Grand Slam or reached the pinnacle of the rankings.
"Everyone is thinking about the possibility of reaching the No. 1 position. That's an extra motivation for all of us," said Dementieva, who reached the semifinals with a 6-2, 6-2 win over Carla Suarez Navarro on Wednesday.
"That's why I guess we're all trying very hard to win this one."
Safina is just trying to focus on the task at hand. "Of course I smell [it]," she said. "But, as I said, if I play my game and I keep winning matches, the ranking will come."
Williams, who has already been there and done that, is more concerned about lifting the trophy.
"I'm all about winning Grand Slams," she said, having held the top spot for 61 weeks during her career. "I'm not worried about being No. 1. I think it's gonna come sooner or later."
She kept her hopes alive by coming back from the brink against Svetlana Kuznetsova on Wednesday. Kuznetsova served for the match in the second set but faltered, and Williams proceeded to run off nine of the next 10 games.
A title would bring her career haul to 10 majors, one more than Monica Seles and three more than the seven currently held by Serena's sister, Venus.
But having Serena Williams back on top would -- at least temporarily -- pause the debate about the perceived weakness of recent WTA No. 1s. Having won two Grand Slam titles and reached the final of a third over the past year, she would have the strongest record of any No. 1 in the past nine months.
Serena had returned briefly to No. 1 after winning the U.S. Open in September, but dropped back after playing few tournaments in the fall.
The sudden retirement of Justine Henin last May created a period of chaos at the top of the rankings, with five different No. 1s (including Henin) over five months. Because Henin decided to remove her name from the rankings immediately, it created a vacuum period during which Jankovic became the first No. 1 never to have gone beyond a Grand Slam semifinal.
The Serb rectified that omission by reaching the U.S. Open final a few weeks later, and secured the season-ending No. 1 with some strong results during the fall season.
Many, however, felt that the player of the year was either Serena or Venus Williams, and Jankovic was under pressure to back up her ranking by winning the title in Melbourne.
Safina does not face the prospect of becoming a Slam-less No. 1, because she must win this tournament to take over the top spot.
Dementieva, however, could end up with that dreaded label if she loses to Zvonareva in the final. It's not something she wants. "It's always nice to become No. 1 by winning something big," she said, with a little laugh.
But whoever ends up on top next week, it's not likely to begin a period of stability at the top of the rankings. Either because of injury or inconsistency, no player on the WTA Tour has recently shown the ability to dominate the field; the past five Grand Slams have been won by five different players.
Serena, Dementieva, Safina and Jankovic will end up as the top four in some order, with all remaining close enough to ensure almost every big tournament will have the potential to affect No. 1.
Maria Sharapova, the defending Australian Open champion who is still sidelined after shoulder surgery, will likely end up just outside the top 15.
Despite the absence of a well-defined hierarchy, the women have put on an entertaining show at the Australian Open. In addition to the excitement of Jelena Dokic's run, there have been several high-quality, dramatic matches involving the top seeds. The big names that did not bring their big games have not survived.
Dementieva sees the flux at the top as positive.
"This is a really unique situation," she said. "There are probably five or six players who can reach the No.1 position by the end of the year. So it's really interesting for me as a player.
"I'm sure it's interesting for the crowd as well to watch this competition, because it's really tight."
Kamakshi Tandon is a freelance tennis writer for ESPN.com.