Djokovic loses in opening round of US Open for first time, falling to Navone

Novak Djokovic, the world's most decorated tennis player, suffered his first opening round defeat at the U.S. Open, losing to rising star Mariano Navone in a five-set marathon. The 39-year-old Serbian grappled with physical and internal ailments, making mistake after mistake and struggling to find his footing under the lights. The match lasted four hours and 36 minutes, the longest opening match of a Grand Slam in Djokovic's career and his earliest exit at the U.S. Open in 24 years.

Djokovic made 70 unforced errors and was seen visibly uncomfortable throughout the grueling contest. After the loss, Djokovic admitted he didn't enjoy himself on the court, stating it was an "awful feeling." The defeat raises questions about Djokovic's future at Grand Slams, given his recent struggles and the toll of sickness and soreness.