Less than two weeks after getting defaulted from the US Open, Novak Djokovic lost his cool again midway through a 6-3, 4-6, 6-3 win over German qualifier Dominik Koepfer in the Italian Open quarter finals Saturday.

When Djokovic was broken at love to even the second set at 3-3, he slammed his racket to the red clay in anger.

India’s Rohan Bopanna and Denis Shapovalov of Canada lost to Frenchmen Jeremy Chardy and Fabrice Martin 6-4, 5-7, 7-10 in the quarter finals.