Tiafoe's heartbreaking French Open collapse ends America's last hope at Roland Garros

Frances Tiafoe was the last American standing at the French Open.

And after leading two sets to one and 5-4 in the fourth set, he was one service hold away from a trip to the quarterfinals. Then he let it slip away.

Tiafoe, the No. 19 seed, lost to Matteo Arnaldi in five sets at Roland Garros, ending the United States' singles run in Paris in brutal fashion.

Arnaldi beat Tiafoe, 7-6 (5), 6-7 (3), 3-6, 7-6 (3), 6-4, to reach the quarterfinals.

This wasn't just a loss.

It was a complete collapse.