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Serena Williams has a special incentive to get to Perth and win the Hopman Cup for a second time, according to her partner, Mardy Fish (she is undefeated in eight matches in the competition).

The winners each receive a diamond-encrusted tennis ball, but she no longer has it. "It’s all she was talking about when we played a charity event together," said Fish. "She said her mom took the one she had from before so she wanted one of those again."