Rafael Nadal hit back from a set down against Mardy Fish to secure a place in the semi-finals of the US Open for the first time in his career, where he will meet Andy Murray who ensured his progress with a four-set win over Argentinean Juan Martin del Potro.
World number one Nadal edged out the unseeded American 3-6 6-1 6-4 6-2 in a match which finished well into the early hours of this morning.
Having shared the opening two sets the match was in the balance but the momentum swung Nadal's way when he broke Fish in the seventh game of the third.
He served it out and continued to hold the edge with a break in the third game of the fourth. Fish displayed his frustration at the next change of ends, smashing his racket on the floor.
The American's annoyance quickly turned to disappointment as he dropped his serve again to fall 5-2 behind.
There was no way back as the Spaniard secured the match at the second attempt when Fish hammered a forehand beyond the baseline.
"I am very happy to be in the US Open semi-finals for the first time," Nadal said. "This court has always been very hard for me."
Fish had captured the first three games in the first set en route to a 5-2 advantage.
After Nadal held, Fish was dominant on his serve and clinched the first set with a sizzling forehand winner.
"Mardy played unbelievable in the first set," Nadal said.
Next up for the 22-year-old is a last-four clash with Murray, who beat Potro 7-6 (7/2) 7-6 (7/1) 4-6 7-5 to secure his first major semi-final berth.
"He is doing very, very well," Nadal said of the Scot. "I expect a very tough match."
Nadal has been the best player in tennis this year and last month he overtook Roger Federer as the world number one, ending the Swiss star's four and a half year reign at the top of the rankings.
The five-time grand slam champion earned that honour just a day after claiming gold at the Beijing Olympics, which marked his ATP-leading eighth title of the year.
Nadal, who also beat Federer to claim his maiden Wimbledon title in July, is now in line to become the first player since Rod Laver in 1969 to win at the French Open, the All England Club and Flushing Meadows in the same year.