Novak Djokovic's run at the U.S. Open came to an abrupt end Sunday night with a stunning first-round defeat to unseeded Mariano Navone. The 39-year-old tennis legend struggled with physical and internal ailments throughout the match, ultimately falling in a five-set marathon that lasted four hours and 36 minutes. This marks Djokovic's earliest Grand Slam exit in two decades, dating back to the 2006 Australian Open, and his first-ever first-round loss at the U.S. Open.

Djokovic, who holds the record with 24 major titles, appeared to be battling significant physical distress during the match. He reportedly threw up at least once, experienced cramping, and grimaced in pain after various shots. During a medical timeout between the fourth and fifth sets, he received treatment for his lower back and took pills. He acknowledged these issues post-match, stating, "It’s something that I’ve been carrying, unfortunately, pretty much every match this year: vomiting, throwing up, a serious issue there. Then my whole body starts to collapse, basically cramping and pain. Yeah, the back just gave up in the end and shoulder, and I couldn’t close it out."

Despite building early leads in the first set, Djokovic made 70 unforced errors and struggled to maintain his form. Navone, a 25-year-old from Argentina who won his first ATP singles title earlier this year, capitalized on Djokovic's difficulties. The younger player expressed his disbelief, calling it a "dream come true" to defeat his idol on such a grand stage.

This defeat follows a challenging period for Djokovic, who also experienced an early exit at the Cincinnati Masters tournament earlier in August. The uncertainty surrounding his physical condition has now cast a shadow over his future participation in major tournaments, leaving fans and analysts to question whether this could signal the end of his Grand Slam career.