Not since Andy Roddick in 2003 has the United States seen one of their own clinch the title, with the golden years of Pete Sampras and Andre Agassi long gone.
But no sooner had Serena Williams (40) taken her leave than Tiafoe emerged to give US fans some hope, executing the biggest upset of the tournament so far with vioctory over second seed Rafa Nadal (36) to stand two wins from the final.
"Slams, crazy things can happen. Especially here in New York," said Tiafoe from Hyattsville, Maryland, whose humble beginnings are already the stuff of legend in tennis.
His parents moved to the United States fleeing the civil war in Sierra Leone in the 1990s and his father worked as an on-site caretaker at the Junior Tennis Champions Center in College Park while his mother, a nurse, worked two jobs.
"Us being around tennis was kind of - gets us getting out of our neighborhood," said Tiafoe.
His father hoped tennis could help provide university scholarship money - unaware that one day his son would captivate the crowd in the stadium named for one of the sport's great pioneers, Arthur Ashe.
"It wasn't anything supposed to be like this," said Tiafoe, whose last Grand Slam quarter-final came in 2019 at the Australian Open.
Tiafoe, who is friends with Williams and grew up watching the American great and her sister Venus (42), wore a hoodie on Monday that listed each of her 23 Grand Slam titles.
Now, win or lose, he carries on her legacy of inspiring the next generation of Black athletes in tennis.
"When I was younger, the reason I said to my dad that I think I could be a professional tennis player is seeing her and Venus battle each other," he told ESPN.
"I said damn, that’s two people who look like me and I can go and do that. That’s unbelievable."
His next hurdle to the Grand Slam final is ninth seed Andrey Rublev (24), who he faces on Wednesday in the last eight. The Russian beat him earlier this year at Indian Wells.
Rublev told reporters he was all too aware of the American's appeal to the Flushing Meadows crowds after Tiafoe harnessed the fans to help him win their third-round meeting a year ago.
"(He is) a tough player," said Rublev. "He will try to use the energy, the crowd to be more pumped, to play better tennis... with him I need to wait for my moment and use it."
