Melbourne: David Nalbandian angrily denied throwing water at an Australian Open staff member on Saturday and vowed to appeal against an USD 8,000 fine imposed following his stormy exit from the tournament.

Nalbandian endured a rollercoaster 4-6, 6-3, 2-6, 7-6 (7/5), 10-8 loss to American John Isner on Wednesday and he was incensed when the chair umpire refused to allow a key Hawk-Eye challenge at the climax of the marathon.

The Argentinian argued on court for several minutes with the umpire, whom he later accused of incompetency. And he was slapped with the hefty fine by organisers who accused of him of hurling water at a tournament worker.

But Nalbandian said he was simply washing his hands when a doctor "incredibly" accused him of splashing water at him.

"I fully deny throwing water after the match I played against Isner," he tweeted. "During anti-doping control, I was washing my hands and the doctor incredibly accused to me of throwing water at him.

"Two injustices -- one inside and another one outside the court. I am going to appeal the sanction."

A tournament official said Nalbandian had up to 10 days after the tournament to lodge an appeal against the fine, which is by far the highest handed out at this Australian Open so far.

It was announced after Marcos Baghdatis was docked $1,250 for smashing four racquets in less than a minute in a sensational tantrum which quickly went viral on the Internet.

Nalbandian received support from Swiss great Roger Federer, who denounced the Hawk-Eye decision as a "stupid call" and called for greater consistency in use of the referral system.

The Argentinian was holding a break point at 8-8 in the deciding set when he was told he was "too late" to request a Hawk-Eye challenge, after the umpire overruled a fault call.

In tempestuous scenes, Nalbandian rowed vociferously with the official and also called the match supervisor on court. But he was told Hawk-Eye was used at the umpire's discretion.

"I mean, it's ridiculous playing this kind of tournament with this kind of umpires. What is this? Why did the ATP do this?" Nalbandian fumed later.

"I mean, can you be that stupid to do that in that moment?"

The 30-year-old Nalbandian, who has been ranked as high as number three and was the Wimbledon runner-up in 2002, has slipped to 87th after a series of injuries in recent years.