Anderson was soon 5-4 ahead, hitting his 100th ace of the tournament in the process before leveling the tie in the 12th game courtesy of a Carreno Busta double fault and a fierce backhand victor.
Anderson, seeded 28th, beat the Spanish 12th seed 4-6 7-5 6-3 6-4 in NY.
Instead of risking injury to play Davis Cup tennis for little or no incentive, Anderson pursued his dream.
The hard-hitting South African has pounded 20 aces, including one at 132 miles per hour to end the set, to just one for Carreno Busta.
Another marathon game on the Spaniard's serve followed, this time with five deuces but Anderson was unable to find a match point opportunity as Carreno Busta narrowly held his serve and forced his opponent to serve out the match.
The likes of fourth seed Alexander Zverev, seventh seed Grigor Dimitrov and eighth seed Jo-Wilfried Tsonga then went out in the early rounds. For this U.S. Open, however, both Djokovic and Murray withdrew because of injury, as did the defending champion, Stanislas Wawrinka, so Anderson acknowledged that "some of them gave us a chance". Anderson hasn't won an ATP title since 2015 and has won 28 and lost 15 matches this year. He played his typical steady, if unspectacular, brand of tennis, earning two winners against just one unforced error.
Anderson always used to be considered a nearly-man, for so long unable to get past the last 16 of a grand slam event, always finding someone just too good on the day.
This time, he takes on those two greats of the game in reverse order: del Potro beat Federer in the quarterfinals Wednesday.
Zuma arrives in China for Brics summit
Modi's visit was announced a day after India and China agreed to disengage their troops from the Doklam plateau in Bhutan. Coincidentally, Myanmar was also the first country that Modi had visited after carrying out his first reshuffle.
Free Netflix on T-Mobile Plans Starting 12th September
AT&T and Verizon reintroduced unlimited data plans early in 2017 to combat market-share gains by T-Mobile and Sprint . T-Mobile USA also made mention that "Like all plans, features may change or be discontinued at any time".
Yarma backs Super Eagles to do the double over Cameroon
It could have been worse for the Black Stars, who lacked offensive cohesion and struggled to deal with the lively Thievy Bifouma. They sit five points behind leaders Uganda after Thomas Partey equalised for them five minutes from time in Kumasi.
United States reasserts 'ironclad' commitment to defend S.Korea
North Korea on Sunday conducted its most powerful nuclear test to date, triggering US warnings of a "massive military response". Fischer wrote: "During this challenging time, we must demonstrate solidarity with our allies as they face significant threats".
Pumped up gas prices may dip slightly
In Vancouver, McKnight predicted little change on the weekend but McTeague says he expects a five-cent jump on Saturday. Gasoline prices are expected to drop two cents a litre in the GTA on Sunday.
5 reasons why Buckeyes will beat Oklahoma
In fact, the biggest concern for the Buckeyes' defense may not be the Sooners' wide receivers, but their playmaking tight ends. When the dust had settled, they had recorded five sacks and two interceptions. " They got us a year ago , " Mayfield said.