The top-seeded Spaniard won a 3-6, 6-1, 6-4, 6-2 victory over Fish after two hours and 40 minutes early on Thursday."I'm very happy for being the first time in the semifinals of the US Open," Nadal said. "Mardy played very well in the first set, served unbelievably well," he added. The 22-year-old Nadal must now compete with British sixth seed Andy Murray in Saturday's semifinals of the year's last Grand Slam tennis tournament.
"It's going to be very difficult. I'm going to have to play my best," Nadal said. "He's coming with big confidence. He's doing very well. I expect a very tough match."