Arguably the best women’s player of her generation, No. 1 Serena Williams is favored to claim the 2015 French Open as the 20th grand slam title of her illustrious career as the clay court tournament begins on Sunday.

Williams is a narrow 5/2 favorite over rivals No. 2 Maria Sharapova and No. 3 Simona Halep, both listed at 4/1, to storm Roland Garros and join the quite short list of all-time greats with 20 or more major titles. Owning a 25-1 record his year, as well as a 17-2 career record over Sharapova, Williams sits at 19 career titles, three back of Steffi Graf and five behind Margaret Court.

Williams already triumphed over Russia’s Sharapova in the Australian Open finals to start the season, earning her sixth title there, and took down Halep in the Miami Open semifinals 6-2 4-6 7-5 last month.

If there’s any reason to doubt Williams at the French it’s her recent spat of injuries this year.

The 33-year-old most recently pulled out of her third round match with Christina McHale in Rome earlier this month due to some type of elbow injury. And despite making her first trip back to Indian Wells in 14 years, Williams withdrew from her semifinal matchup with Halep with a knee injury.

Hall-of-Famer Martina Navratilova recently told Tennis Podcast she thinks Williams recognized her career might be declining, and that she rededicated herself to the sport, coincidently, after her first round exit at the French in 2012.

"Serena is amazing, and she will get to 20 slams for sure," Navratilova said. "She put her career into another gear three years ago after that loss to Virginie Razzano at the French Open. She really focused herself on the sport.

"She realised that her time was running out and that if she wanted to make her mark on the sport she had better get going, and she has barely lost any matches since then."

Williams already owns two French titles, but it’s a far lower total when compared to her success at the three other slams. Williams has six U.S. titles and five she attained from Wimbledon. But after winning the French in 2013, Williams’ title defense was quickly dashed with a 6-2 6-2 crushing in the second round from then-unranked Garbine Muguruza. Before the 2012 debacle, Williams had at least reached the French quarters seven out of eight times, but usually fell.

Turning to defending champion Sharapova, the 28-year-old can’t escape the fact that Williams has defeated her 16 straight times. The last time Sharapova beat Williams was in 2004, at the Tour Championships and Wimbledon finals.

But after her victory in the Rome finals over No. 10 Carla Suarez-Navarro secured her an easier road to the late stages of the French, Sharapova could have enough momentum to edge out Williams on her least favorite surface.

Romania’s Halep, whose gone 29-6 with three titles this season, has slipped of late. She fell to Suarez-Navarro in the Rome semis and No. 4 Caroline Wozniacki in the semis at Stuttgart after a first-round exit in Madrid. However Halep did push Williams to the brink in Miami before dropping 2-6 6-4 5-7, and she’s a 23-year-old rising star who reached the French finals last year before running into Sharapova.

Odds via

Serena Williams 5/2

Maria Sharapova 4/1

Simona Halep 4/1

Victoria Azarenka 7/1

Petra Kvitova 10/1

Carla Suarez Navarro 16/1

Caroline Wozniacki 18/1

Garbine Muguruza 18/1

Eugenie Bouchard 20/1

Angelique Kerber 25/1

Ana Ivanovic 33/1

Sara Errani 33/1

Agnieszka Radwanska 40/1

Andrea Petkovic 40/1

Karolina Pliskova 40/1

The full list can be found here