Coria said the men's ATP Tour and the International Tennis Federation (ITF) had made a mistake and accused them of being out of touch.

"Canas is not a criminal. He didn't kill anyone," Coria told Reuters. "I know him very well and he would never take anything to give himself an advantage. It was an accident."

Coria added: "I hope CAS (the Court of Arbitration for Sport) will reduce the suspension. It will be very difficult for him to come back after two years. He will be 29.

"The ATP and ITF must look at things more on a personal level and less in black and white."

Also Read Canas banned for two years for doping Canas justifies top ranking

Canas last month became the latest Argentine, including Coria himself, to be banned for doping by the ATP in recent years.

The 27-year-old Canas tested positive for the prohibited diuretic hydrochlorothiazide (HCT) in Acapulco this year. He said he had taken medicines given to him by tournament officials with the ATP's knowledge.

Coria, playing at the China Open in Beijing [Images] this week, said it was unfair to ban Canas from attending next week's Davis Cup semi-final with Slovakia in Bratislava.

"It's a bad rule and all the players are against it," fumed Coria, who was banned for seven months in 2002 after testing positive for nandrolone.

"We think it's ridiculous he can't be there with us. He's very important to the team. It's incredible. The rules need to be changed."

However, Coria expects Canas to come back after his ban.

"He's always fought for his goals. He always left everything on court and off the court he's a fighter," said Coria. "I'm sure he'll be back."

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