NEW YORK (Reuters) - Andy Murray double-faulted to send the match to a fourth set, but then swiftly took care of business in a 6-1 7-5 4-6 6-2 win over Russian Andrey Kuznetsov to reach the fourth round of the U.S. Open on Saturday.
The eighth-seeded Murray, who suffered from cramping during his first-round win, had his stamina tested again in a groundstroke battle against the unseeded Russian on a humid day in Flushing Meadows, but came through in good shape.
"He played some good stuff at the end of the second set and all the through the third," Murray said. "I just tried to stay solid in the fourth set and thankfully it paid off.
"I feel better than I did in the first match, obviously. I made sure I did everything properly. I ate properly, drank properly and I felt a lot better today."
Murray, the 2012 U.S. Open winner and last year's Wimbledon champion, will next play either ninth-seeded Frenchman Jo-Wilfried Tsonga or Pablo Carreno Busta of Spain.
(Reporting by Larry Fine; Editing by Gene Cherry)