Margaret Court - With 24 Grand Slams, Court is No. 1 on the all-time list, though just over half of those titles came before the Open Era when there was a smaller pool of top-level competitors at the majors. An impressive athlete, she won the calendar Grand Slam in 1970, becoming the first woman in the Open Era to pick up all four Slams in the same year.
Steffi Graf - One of the true legends of the sport, Graf holds 22 major singles titles, the most of any male or female in the Open Era. Her 22 trophies were fairly spread out between all four majors - four from Melbourne, six in Paris, seven in London, and five at New York. In 1988, Graf won all four Slams and an Olympic gold to become the only person to ever achieve the calendar year Golden Slam.
Chris Evert/Martina Navratilova - With her victory on the weekend, Williams surpassed Evert and Navratilova on the list. With 18 Slams each, these two famous friends and rivals are among the best to ever pick up a racquet. What's probably most impressive about their feat is they were both able to hit 18 Slams during the same era.
Now just three Slams behind Graf, 33-year-old Williams is targeting history. The three-time Rogers Cup presented by National Bank champion definitely has a strong shot of reaching 22, as the world No. 1 has few peers on the WTA circuit who are capable of beating her when she's at her best.
"I would love to get to 22," she said in her post-match press conference following the Australian Open final. "I mean, 19 was very difficult to get to, it took me 33 years to get here. I would love to get there, but I have to get to 20 first, and then I have to get to 21. There are so many wonderful young players coming up, so it will be a very big task. My next goal was just to get to 19. That was my goal. So I didn't think it would happen this fast, to be honest, but it feels really good."
One of the most exciting storylines this season will indeed be if anyone can stop Williams at the Slams. Sharapova, who is third among active players with five Slam titles (Venus Williams has seven), is the defending champion at Roland Garros and will certainly be looking to add to her total. Petra Kvitova and Victoria Azarenka are both two-time Slam winners and have the drive and talent to go beyond that. And there are also a few athletes capable of winning their first in the near future - Simona Halep, Caroline Wozniacki, Agnieszka Radwanska, and Canada's own Genie Bouchard to name a few.
But if her performance over the past two weeks in Melbourne is any indication, Williams will again be a force at the French Open, Wimbledon, and US Open. While she already solidified her place in the history books years ago - she won her first Slam at the 1999 US Open and now holds six Aussie Open crowns, two French Opens, five Wimbledon trophies, and six US Open titles - Williams has a lot of tennis left in her and the journey to 22 will be a fun one to watch.