While Serena Williams (rightfully) stole the headlines at the 2022 U.S. Open in New York, it's time to move on to the next biggest story in tennis: U.S.A's very own Frances Tiafoe.

The 24-year-old American, who was ranked 22nd at the U.S. Open, served up arguably the biggest upset of the tournament, beating the No. 2-ranked Rafael Nadal in four sets (6-4, 4-6, 6-4, 6-3) in the Round of 16 on Monday.

With the upset, Tiafoe becomes the youngest American tennis player to reach the U.S. Open semifinals since Andy Roddick in 2004, according to the ATP Tour.

Tiafoe also becomes the first American tennis pro to defeat the 36-year-old Nadal since James Blake did so in 2005.

This is Tiafoe's second time reaching a quarterfinal in a grand slam tournament. He reached the quarterfinals at the Australia Open in 2019 before losing.

Tiafoe came into the match extremely confident that he could beat Nadal.

“I’m not going to have that first-time-playing-him, excited-to-play [feeling],” Tiafoe said prior to the match with Nadal. “Now I believe I can beat him.”

While Nadal almost assuredly wasn't 100 percent healthy after undergoing abdominal surgery which forced him to withdraw from the semifinals of this year's Wimbledon, he has been on a hot streak this season, emerging victorious at the French Open and Australian Open this year.

Tiafoe will next face ninth-ranked Andrey Rublev on Wednesday, Sept. 7, in the quarterfinals. The time of the match has yet to be announced.

Will Tiafoe be able to reach the semifinals, and perhaps be crowned champion? We'll find out as the U.S. Open rages towards its conclusion.