After closing out the match on his serve, Anderson climbed over a flower pot and into the stands to hug his wife, Kelsey, and others in his player's box.
"It was an unbelievably tough match on one of the biggest stages in tennis". I think just my emotion at the end summed it up.
"I'm over the moon". "It was really nice that they came out and watched me".
Carreno Busta surrendered a 40-0 advantage in his next service game, which went to deuce five times before he eventually held to force Anderson to serve for the match.
They also met in the 2009 semifinal at Flushing Meadows, when del Potro routed Nadal before beating Roger Federer for the title.
"To be honest, I'm angry to lose a chance like this but maybe tomorrow I will be calm and see how big the tournament was for me".
By reaching this point - and at the time of writing Anderson was yet to play his semi-final - he has done more for South African tennis than he would have playing in the third tier of the Davis Cup.
He is 1/8 with Sky Bet to do so against first-time finalist and 5/1 shot Anderson, who was the man to take advantage of the open bottom half of the draw.
The No. 28 seed Anderson had been broken only three times in his first 90 service games in the tournament.
This is the second Grand Slam title for Tecau and Rojer, who won Wimbledon in 2015.
Anderson, 31, admitted that he was stunned to have risen from 80th in the rankings in January when he appeared destined for hip surgery and a lost season in recovery.
But despite a series of injuries, from shoulder to knees and at the end of past year, to his hip, he has bounced back brilliantly to put his name in the history books.
If you were to look at pre-tournament form as a guide, then Carreno Busta doesn't even rate a mention with early exits in Montreal and Cincinnati. Sloane Stephens will meet #Madison Keys for the women's crown at 2017 US Open. He committed 14 unforced errors to just one for Carreno Busta in the set. Carreno Busta double faulted to give him the set. He took the set when the Spaniard double-faulted at 5-6, 30-all and Anderson then smacked a forehand victor into the corner on set point.
Should Anderson prevail, he will be the first South African man in a major final since Kevin Curren finished runner-up at Wimbledon in 1985.