Croatia's Marin Cilic lost in five sets to Japan's Kei Nishikori in a match lasting a minute short of five hours.

The second set alone lasted an hour and 17 minutes and the fourth an hour and 13 minutes as world number 147 Nishikori recovered from two sets to one down to win 5-7 7-6 (8/6) 3-6 7-6 (7/3) 6-1.

Both players understandably struggled in the heat and Nishikori said: "I don't know how long I played, I'm pretty tired of course.

"I was cramping from the second or third set but I kept fighting and fighting and that fourth set tie-break was key for me.

"It was a great match. It was hot but I am feeling great now."

Cilic, the 11th seed, joins the list of big-name casualties at the US Open which includes sixth seed Nikolay Davydenko who was sent packing by France's Richard Gasquet.