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Serena Williams vs. Daniela Hantuchova (2007)
Serena Williams had cruised in the first set of her fourth-round match against Daniela Hantuchova in 2007, winning 6-2, but the rest of her match wouldn't be nearly as easy. Williams collapsed in the second set with crippling muscle cramps in her left calf muscle, screaming in pain. After trying to stand a few times and having her leg buckle underneath her, Williams finally got to her feet to continue the match. With her movement incredibly limited, she barely moved when returning Hantuchova's serve and, with tears rolling down her cheeks, gingerly hit her shots. She was saved by the rain just minutes later, however, trailing 2-4 in the second-set tiebreak. The two-hour delay was enough for Williams to somewhat recover, and although she lost the second set she gutted her way to a 6-2 final-set victory.

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