Friday February 28th, 2014

In this edition of Tweets of the Week, Novak Djokovic takes to the air, Juan Martin del Potro shows off his childish side and Serena Williams starts the trash-talking. Here are some of the best of this week's Twitter dispatches.

(The four are set to play an exhibition match this weekend)

(Stepanek went on to lose the match 6-2, 6-7, 6-3).

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