With the remnants of Tropical Storm Hanna expected to roll through the New York area for the rest of the day, play was suspended for the day and the match will resume on Sunday, weather permitting.

Murray, serving powerfully and dominating the Spaniard from the baseline with his deeper groundstrokes, swept through the first set in just over half an hour before clinching the second 7-5 in a tiebreak.

The Scot, competing for the first time in the last four at a grand slam, had ripped 44 winners past Nadal, including 17 aces, when their match was forced into a second day.

Left-hander Nadal, the French Open and Wimbledon champion, has not lost to the Scot in five previous meetings but, like his opponent, was competing in his first US Open semi-final.

Sixth seed Murray was bidding to become the first Briton since Greg Rusedski in 1997 to reach the US Open final.

Whoever wins will play four-times defending champion Roger Federer in the final, the Swiss master having battled past Serb Novak Djokovic 6-3 5-7 7-5 6-2 earlier Saturday.

Murray, a winner of three ATP titles this season, broke Nadal in the third game of the match when the Spaniard hit a forehand long and again in the seventh with a forehand pass down the line to lead 5-2.

With threatening rain clouds looming, the 21-year-old Briton served out to wrap up the first set in 33 minutes after Nadal netted a backhand pass.

It was the first time the Scot had won a set against Nadal since their first encounter at the 2007 Australian Open.

Nadal had to work hard to hold serve in the second, saving two breakpoints in the fifth and 11th games before the set went into a tiebreak.

After an early exchange of mini-breaks, Murray clinched it 7-5 when the struggling Nadal hit a backhand wide.

Against the run of play, the Spaniard broke Murray in the first game of the third set when the Briton hit a forehand long.