The Spaniard was surprisingly untroubled for most of the match, closing it 6-2, 6-1, 6-3 in under two hours. Nadal next faces Andy Murray, who defeated American hope John Isner in four sets 7-5, 6-4, 3-6, 7-6 (2).
All top-four players in the world have once again reached the semifinals of a Grand Slam event, after achieving the feat at the French Open earlier this year.
Here's a preview of the matches:
Roger Federer, in the semifinals of the US Open for the eighth year in a row, squares up against Novak Djokovic in the first of the men's semifinals.
Federer holds a 14-9 head-to-head record against Djokovic and will be looking to add to that. The last time the two met, in the semifinal of the French Open in Paris earlier this year, Federer was the victor in four sets in a match that lasted over three hours.
What will the US Open final line-up be?
Why Djokovic could win? Novak is ultimately more consistent than the aged Federer.
Why Federer could win? Roger's high tempo style doesn't suit Djokovic.
Winner? Federer. The downside to Novak Djokovic winning as much as he has so far this year, is that he has accrued more mileage than his biggest rivals. As such, burnout has seemed an ever more obvious problem as Novak has progressed through this tournament.
Federer is more clinical than the players that Djokovic has played so far, and the lethargy that Djokovic exhibited against previous opponents should be punished severely.
Andy Murray (4) vs Rafael Nadal (2)
In a matchup that sees the remainder of the top four in the world squaring off, Andy Murray will face Rafael Nadal for the second time in a US Open semifinal.
Nadal holds a 12-4 head-to-head record against Murray, with all of Murray's wins coming on hard courts. The two men last met in the semifinal stage of Wimbledon this year, with Nadal winning in four sets.
Why Nadal could win? Nadal is fresher, stronger and is the more potent of the two players.
Why Murray could win? Murray knows Nadal's weakness, can execute a game plan to target that weakness, and has succeeded in the past.
Winner? No idea. It will be a battle between Nadal's forehand and Murray's backhand. The stats to watch will be the first and second serve points won.
Between the two "underdogs" in this tournament, it is not clear what to expect.