Seeds

1.   Novak Djokovic
   Novak Djokovic
   Novak Djokovic is a Serbian professional tennis player who has been ranked world no. 1 by the Association of Tennis Professionals since 4 July 2011. He has won four Grand Slam singles titles: the 2008 and 2011 Australian Open, the 2011 Wimbledon Championships, and the 2011 US Open...
   
    (Round Robin)
2.   Rafael Nadal
   Rafael Nadal
   Rafael "Rafa" Nadal Parera is a Spanish professional tennis player and a former World No. 1. , he is ranked No. 2 by the Association of Tennis Professionals...
   
    (Round Robin)
3. Andy Murray (Round Robin, withdrew due to a groin injury)
4.   Roger Federer
   Roger Federer
   Roger Federer is a Swiss professional tennis player who held the ATP no. 1 position for a record 237 consecutive weeks, and 285 weeks overall. As of 28 November 2011, he is ranked World No. 3 by the Association of Tennis Professionals . Federer has won a men's record 16 Grand Slam singles titles...
   
    (Champion)

5.   David Ferrer
   David Ferrer
   David Ferrer Ern is a Spanish professional tennis player who lives in Valencia, Spain who is currently no. 5 in the ATP Rankings and the second-highest ranked Spaniard behind world no. 2 Rafael Nadal. He turned professional in 2000...
   
    (Semifinals)
   
6.   Jo-Wilfried Tsonga (Final)
   
7.   Tomáš Berdych
   Tomáš Berdych
   Tomáš Berdych is a professional tennis player from the Czech Republic. His most notable achievements are reaching the final of the 2010 Wimbledon Championships, and the semifinals of the 2010 French Open. He defeated the Croatian player Ivan Ljubičić in five sets to win the Paris Masters in 2005...
   
    (Semifinals)
   
8.   Mardy Fish
   Mardy Fish
   Mardy Simpson Fish is an American professional tennis player, and Olympic silver medalist. He is a hardcourt specialist...
   
    (Round Robin)
   
   

   Alternates

   
   
   9.   Janko Tipsarević
      Janko Tipsarevic
      Janko Tipsarević is a Serbian tennis player. His career-high ranking is No. 9, achieved on 14 November 2011. He is the 117th player in history to crack the top 10....
      
       (Replaced Murray, Round Robin)
      
      
      
      
      10.   Nicolás Almagro
          Nicolás Almagro
          Nicolas Almagro Sanchez Rolle is a professional Spanish tennis player, ranked 10 on the ATP World Tour.-2005:...
          
           (Not used)
          
          

          Finals

          Group A

          Standings are determined by: 1) Number of wins; 2) Number of matches; 3) In two-players-ties, head-to-head records; 4) In three-players-ties, percentage of sets won, or of games won; 5) Steering Committee decision.
          

          Group B

          Standings are determined by: 1) Number of wins; 2) Number of matches; 3) In two-players-ties, head-to-head records; 4) In three-players-ties, percentage of sets won, or of games won; 5) Steering Committee decision.
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