Ben Shelton hopes he can inspire young people to "develop a passion for tennis" after booking his place in the US Open quarter-finals.
The American shocked fellow countryman and 14th seed Tommy Paul 6-4 6-3 4-6 6-4 on Arthur Ashe Stadium.
The 20-year-old sent down the fastest serve of this year's tournament at 149mph and showed an impressive array of shot-making to overpower Paul.
"Being in front of an American crowd, I felt the love all week," he said.
Shelton will face either 10th seed Frances Tiafoe or Rinky Hijikata in the last eight.
He is bidding to become the first American man to win the US Open singles title since Andy Roddick in 2003.