Novak Djokovic does not know if his troublesome elbow injury will require another lay-off, but he reserved credit for Hyeon Chung following his Australian Open defeat to the brilliant youngster.

The six-time champion was beaten 7-6 (7-4) 7-5 7-6 (7-3) in the fourth round in Melbourne as Chung took full advantage of the ailing former world number one, who had returned to action at the tournament after six months out.

Djokovic, wearing a protective sleeve on his right arm, required treatment between the first and second sets, and revealed that he struggled beyond that point. "Unfortunately, it's not great," he said of his injury. "At the end of the first set, it started hurting more so I had to deal with it until the end of the match.

"I played four matches here. It's a good tournament, of course, and it's disappointing to go out in the fourth round, but the circumstances are such and I have to accept it.

"It's frustrating when you have that much time and you don't heal properly, but it is what it is. I'm just trying my best because I love this sport. I enjoy training, I enjoy getting myself better and performing, competing. It was one of those days where it was too much to deal with."

Asked he requires another lay-off, Djokovic responded: "I really don't know. I have to reassess everything with my medical team and coaches.

"We have to scan it and see what the situation is like. In the last few weeks, I have played a lot of tennis."

Chung referred to the Serbian as his "idol" after sealing an unexpected victory, and Djokovic was glowing in his praise of his opponent's performance."It was an amazing performance," Djokovic said. "[Chung] was the better player on the court and he deserved to win, no question about it.

"Whenever he was in trouble, he came up with some unbelievable passing shots. From the back of the court, he was like a wall. It was impressive and I wish him all the best."