Australian Open: Novak Djokovic Calls Out Heckler, Yells Back 'Come Down and Say it To My Face' | WATCH

Novak Djokovic was involved in a fiery altercation with a fan in the stand during his during a testing second-round encounter at the Australian Open against home favourite Alexei Popyrin on Wednesday.

After the match, Djokovic said the angry altercation with the fan may have helped get him over the line .

The world number one showed his trademark mental strength to face down his inspired opponent, prevailing 6-3, 4-6, 7-6 (7/4), 6-3 in more than three hours.

It followed a gruelling first-round match on Sunday, when he was kept on court for more than four hours by teenager Dino Prizmic, admitting afterwards he was “a bit under the weather”.

The Serbian got drawn into a testy exchange with a spectator on Rod Laver Arena early in the fourth set on Wednesday.

“There were a lot of things that were being told to me on the court… I was tolerating it for most of the match,” he said.

“At one point I had had enough, and I asked him whether he wants to come down and tell it to my face.

“When you confront somebody, unfortunately for him, he didn’t have the courage to come down.

“That’s what I was asking him. If you have courage, if you’re such a tough man, tough guy, come down and tell it to my face, and let’s have a discussion about it.”

The top seed was asked whether the argument had fired him up.

“Maybe that was needed,” he said. “I don’t know. Look, I don’t want to be in those types of situations. Yeah, I was flat I guess emotionally.

“Game-wise I was quite flat for some part of the match, end of second set, most of the third set.

“Maybe that was needed for me to be shaken up a bit and start to find the kind of intensity on the court that I needed to have all match.”

Djokovic’s form will offer some hope to his third-round opponent, Argentina’s Tomas Etcheverry.

“I was feeling a lot of mixed emotions on the court, not a great atmosphere to play in for me,” Djokovic told Eurosport.

“It’s frustrating when you have the hecklers.”

Asked about his physical condition, a sniffly Djokovic said: “I don’t want to get into the details about how I feel, but not feeling my best. But I’ve been in this situation many times.”