Nadal overwhelmed Juan Martin del Potro, 4-6, 6-0, 6-3, 6-2; Anderson, 31, beat Pablo Carreño Busta, 4-6, 7-5, 6-3, 6-4, to reach his first Grand Slam final.
Closing in on a 16th Grand Slam title, the top-seeded Spaniard overcomes a so-so start with an overwhelming performance the rest of the way, taking nine games in a row during one stretch.
Rafael Nadal will play for his 16th Grand Slam title in the U.S. Open final.
US Open semifinals: Rafael Nadal vs Juan Martin del Potro; Pablo Carreno Busta vs Kevin Anderson
Tennis Channel breaks down the men's semifinals at the U.S. Open, where Rafael Nadal defeated Juan Martin del Potro and Kevin Anderson beat Pablo Carreno Busta.