Britain's Murray dropped the first set but then recovered to post a 5-7, 6-2, 6-1, 7-6 (9-7) victory over Tomas Berdych of the Czech Republic, putting him in position for his first Grand Slam title. The Scotsman is 0-4 in his previous Grand Slam finals.
Murray started sluggishly after an hourlong rain delay and appeared to struggle with strong winds that buffeted the New York venue. But he had little trouble over the middle two sets, never facing a break point.
Berdych jumped out to a 3-0 lead in the fourth-set tiebreak before Murray rallied again for the match.
Ferrer had grabbed a 5-2 lead in the first set Saturday, but play was suspended because of the continuing weather problems.
Tournament officials said Djokovic-Ferrer match would resume 11 a.m. EDT Sunday, with the men's final now set for Monday -- marking the fifth straight year in which the men's title match has been held a day late.