Kyle Edmund gave Leon Smith's team the perfect start by beating Feliciano Lopez – a very late substitute for Pablo Carreno Busta – 6-3 7-6 (3) but Evans was unable to pull off a miracle as he went down 6-4 6-0 against the world number one.
Nadal has not lost a Davis Cup singles match since his debut in 2004, winning 26 in a row before this one, so it was clear what a monumental task this was.
For nine games, Evans played about as well as he can, sticking with Nadal from the back of the court, serving well and coming forward intelligently.
But, once Nadal broke to win the first set, it was one-way traffic, setting up a deciding doubles rubber.
This time it was no surprise to see Andy Murray left on the bench after the performances of Edmund and Dan Evans in steering Britain to victory over Germany on Friday.
Edmund had expected to face Carreno Busta only for Spain to make a switch just five minutes before the start when he was ruled out with a thigh injury.
The timing certainly raised eyebrows given rumours were circulating about the fitness of Carreno Busta on Friday evening but Edmund, unfazed, powered to a 6-3 7-6 (3) victory to put Leon Smith's side within one rubber of a final against Canada.
Edmund said afterwards: "Busta actually came to warm up, (he was) on the bike (for) two minutes, he left. I said straightaway, 'Something is a bit weird there'. Then straightaway the guy came in.
"I think they knew what was going on but they just sort of went to the rules, they could do that. And yes, as soon as I found out, there's no point trying to argue it, Feli is the guy I was playing.
"And I was good within myself, how I was feeling. I was just enjoying going out to the semi-finals of a Davis Cup against Spain. I knew it was going to be loud out there. And it almost, in a way, it didn't matter who I was playing, I was just concentrating on being me first and putting myself out there.
"And I dealt with it really well, I thought."
Appeals by Murray and the British team and a through-the-night effort from the Lawn Tennis Association brought an extra 800 fans to Madrid for the clash.
The LTA invested more than £60,000 of the considerable prize money it will receive in purchasing tickets and then offering them free to any British supporters who could get to the Spanish capital.
The visiting fans were, of course, still heavily outnumbered in the 12,500-seat stadium – a big contrast from the small arenas in which Britain had played their first three matches.
If Spain had hoped the late change might disrupt the exceptional rhythm Edmund has been in all week, they were quickly disabused of that notion.
The Yorkshireman began the match with three aces and won eight of the first nine points to claim an immediate break of serve.
Lopez, who had not played a Davis Cup singles match since 2016, freed himself up as the first set went on, with his big serve keeping Edmund at arm's length, but did not force a break point.
The British number three was again in remarkable form for a player who only ended an eight-match losing run a few weeks ago, serving strongly and powering away winners.
Edmund is known for his destructive forehand but his backhand has been the revelation of this tournament and he used it very well again here.
The Lopez serve and the fervent atmosphere were ramping up the pressure on Edmund, though, and a forehand powered just wide gave the Spaniard two set points at 4-5 in the second set.
Edmund kept his nerve superbly, though, sending down big serves to save them both, and was much the better player in the tie-break.