Poorly Djokovic crashes out of US Open first round

The 48th-ranked Argentine's 7-6 (7/5), 5-7, 4-6, 6-2, 6-1 victory ended Djokovic's latest bid for a record 25th Grand Slam title, the monumental achievement looking ever less likely for the 39-year-old.

It also ended his run of 78 Grand Slam first-round victories, a streak stretching all the way back to Djokovic's 2006 loss to Paul Goldstein at the 2006 Australian Open.

"I think it was obvious that it was an awful feeling on the court for me," said Djokovic, who vomited several times and battled late-match cramps.

"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.

"The back just gave up in the end and shoulder, I couldn't close it out."

Djokovic, who took medication during the match, appeared to have finally taken control when he broke Navone for a 2-1 lead in the fourth set with a vintage backhand winner down the line.

But Navone won the next five games, raising his arms in celebration after fighting off two break points for a 5-2 lead and breaking Djokovic again to force the fifth.

Djokovic took a medical timeout before the final set, receiving massage on his spine and more medication.

But Navone jumped to a 3-0 lead in the decisive set and despite the urging of fans there was no road back for the Serb as his opponent dropped just one point on his own serve as he sprinted to the finish line.