Novak Djokovic looked to be cruising to another win at the Australian Open as he chases a ninth title at Melbourne Park.
That all seemed to come unstuck when he slipped on the Melbourne logo at the back of the court.
The defending champion took time out for an injury treatment.
On his return to the court the world no. 1 was not rotating through his shots and his serve had dropped 10 km/h in average speed.
At the time of his injury, Djokovic was up two sets but then Fritz would come back into the match winning the next two.
It would looking ominous for the defending champion but he found a way to lift and in the sixth game he got a break of serve. From there he powered home to a famous victory.
The match had started with a crowd in the stadium but at 11:30 pm they were forced to head home.
As Djokovic secured the win he let out an almighty roar.
Speaking after the match he was not sounding confident of even taking to the court for his round four clash with Milos Raonic, a player he holds an 11-0 record.
“I don’t know if I’ll manage to recover from that in less than two days,” he said of the injury. “I don’t know. I don’t know if I’m gonna step out onto the court or not.
“I was just trying to focus on what’s going on with an injury. Right now, I know it’s a muscle tear,” admitted the top seed