Japan's Kei Nishikori has revealed that the rain delay during his US Open quarter-final match with Andy Murray helped him to change tactics before eventually going on to win the contest in New York.

The sixth seed produced a memorable display after the roof had been closed to upset the odds, having come from behind to claim a 1-6 6-4 4-6 6-1 7-5 victory in three hours and 57 minutes.

"It was too exciting on the court, but I tried to stay calm," said Nishikori, according to BBC Sport.

"I didn't start well - he has a great return - but I finished well.

"The rain delay helped me to change tactics. I tried to hit a few more drop-shots than usual today and it worked really well."

Murray's defeat saw the Scot surrender to his earliest Grand Slam exit of the year.