Kostya Tszyu has told Sergey Kovalev to stop blaming the judges for his defeat to Andre Ward and learn from the experience.
Kovalev lost to a unanimous decision in Las Vegas on Saturday night with American Ward a point ahead on all three scorecards but blamed his defeat on "politics" and the fact that all the judges were American.
However, former three-time world super-lightweight champion Tszyu dismissed the idea that his compatriot should have won on the cards, despite putting Ward down in the second round.
"I was very much rooting for him," he told Allboxing.ru.
"I took great pleasure in watching how he won his fights but in this fight with Ward, something went wrong.
"I would not be so straightforward [to call it robbery]. If the fight took place in Russia or on neutral territory Ward would be unlikely to get such assessment from the judges.
"But the fight was held at the home of Ward, where he is a legend, the idol of millions. Therefore it was necessary for Sergey to win in a manner where no one would have even the minimum amount of doubt.
"To be honest, I did not like the previous fight with Sergey in Ekaterinburg. In the confrontation with Isaac Chilemba he did not look as confident as he usually is.
"It seems to me that he hasn't learned all the lessons from the battlefield, which negatively affected him in the confrontation with Ward.
"When I lost my first fight with Vince Phillips in 1997, I then began to search for the reason in myself and didn't spend time addressing the judges and the referee.
"I asked myself the question: what did I do wrong? And in the end I found my weaknesses, worked hard on them and regained all of the titles."
Following his loss to Phillips, Tszyu went on a 13-fight unbeaten run to become the undisputed 140lbs champion but retired after losing his IBF title to Ricky Hatton in Manchester in June 2005.
And although he was critical of his friend's first defeat, he does believe Kovalev can bounce back.
"I changed a lot, especially mentally, and began to think very different in several aspects," Tszyu said.
"I am convinced that Kovalev could do the same. He needs to understand himself and not to look for reasons to analyse the judges. If he does that, then he will find those mistakes that prevented him from winning early on against Ward.
"He will analyse, change something in himself and therefore he won't give away an opportunity - neither to the Americans, or the judges or the critics."
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