MADRID, SPAIN - MAY 10: Novak Djokovic of Serbia looks on during day five of the Mutua Madrid Open tennis at La Caja Magica on May 10, 2017 in Madrid, Spain. (Photo by Clive Rose/Getty Images)
MADRID, SPAIN - MAY 10: Novak Djokovic of Serbia looks on during day five of the Mutua Madrid Open tennis at La Caja Magica on May 10, 2017 in Madrid, Spain. (Photo by Clive Rose/Getty Images)