Four of the potential contenders for this year's ladies title at the Dubai Duty Free tennis championships.
Angelique Kerber (Germany)
25 years old, No 5 seed
She started 2012 as the world No 32 but ended it No 5. Between the French Open and the end of the season, she was the only person to defeat Serena Williams. She made the quarter-finals at the French Open and was a semi-finalist at Wimbledon. She will be keen to build on her growing reputation and prove she belongs among the elite.
Samantha Stosur (Australia)
28 years old, No 7 seed
She has reached the quarter-final stage in the past two years in Dubai. She made it to the last eight in Doha, as well, last week and will be aiming to improve on that show in Dubai after a poor start to the year, when she lost in the first round at Sydney and Brisbane, and the second round of the Australian Open. She won the US Open in 2011, defeating Serena Williams, and was a French finalist in 2010.
Marion Bartoli (France)
28 years old, unseeded
Aside from 2007, she has come to Dubai every year since 2005 despite never making it past the last 16. A first-round casualty last year, she will be hoping to make the best use of her wild card this time. Serena Williams awaits in the second round, but Bartoli has beaten her before. Six of her seven victories have come on hard courts, and the other was on grass. A US Open quarter-finalist in 2012.
Sloane Stephens (USA)
19 years old, unseeded
Her run to the semi-finals of the Australian Open last month suggested the American teenager might be ready to join the game's elite. She lost in the second round in Doha, however, to Klara Zakopalova. She opens today against Sorana Cirstea, and if she is to reach the final she likely would have to defeat Sara Errani, Victoria Azarenka and Angelique Kerber.