• Title favourite defaulted during first set after losing serve
• Player dismissed after discussions with tournament officials
  

Novak Djokovic was thrown out of the US Open in sensational circumstances on Sunday night when he inadvertently struck a line judge with a dead ball towards the end of the first set of his fourth-round match against the Spaniard Pablo Carreño Busta.

The world No 1, who appeared to hit the ball away casually and with no great force, was distraught as he comforted the woman after she had collapsed in a coughing fit holding her throat. He then engaged in a fruitless 10-minute discussion on court with the tournament referee, Soeren Friemel.