CINCINNATI, OH - AUGUST 20: Karin Knapp of Italy reacts during her match against Serena Williams on Day 6 of the Western & Southern Open at the Lindner Family Tennis Center on August 20, 2015 in Cincinnati, Ohio. (Photo by Maddie Meyer/Getty Images)
CINCINNATI, OH - AUGUST 20: Karin Knapp of Italy reacts during her match against Serena Williams on Day 6 of the Western & Southern Open at the Lindner Family Tennis Center on August 20, 2015 in Cincinnati, Ohio. (Photo by Maddie Meyer/Getty Images)