Bolton winger Martin Petrov insists he is not surprised by the electric recent form of Dimitar Berbatov, and says he knew it was only ever a matter of time before his former Bulgaria team-mate found his goalscoring touch for Manchester United.
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Berbatov has come under fierce criticism from fans and pundits alike during his two years at Old Trafford, having failed to replicate the prolific form that persuaded Sir Alex Ferguson to part with a club record £30.75 million for him in August 2008.
But the United striker has silenced his critics with a fantastic start to the new season and he currently sits atop the Premier League scoring charts with six goals from five games, including a sensational match-winning hat-trick against Liverpool last week,
And Petrov, who played alongside Berbatov for more than a decade in the Bulgarian national team and will line-up against his former team-mate when United visit Bolton on Sunday, says he ever doubted his friend's ability.
"He is on fire," Petrov told ESPNsoccernet. "For me, it's not surprising because we played together in the national team. In his the first two years I think he just needed to be given a little bit of time.
"With respect to Tottenham, United are one of the best teams in the world and I think he needed time to settle. Now he shows what he can do - score beautiful goals and play fantastically - I am happy for him and disappointed I don't play with him in the national team any more."
Berbatov announced his retirement from international football in May and revealed his decision was motivated by a desire to improve his performances for United. But Petrov is unsure whether stopping playing for Bulgaria has helped Berbatov's form, and believes the problem was most likely a confidence issue.
"Maybe [international retirement has helped him], everyone tells me that," Petrov said. "When he retired he started to score goals and play well for United, but I think really he played well before he just needed to score more - everyone can see he has very good technique and the last part was to score goals.
"Maybe he has cleared the national team from his head and I think everything is great now for him. We didn't speak [about his previous form] because it is a personal thing, maybe he speaks to his family about that - I also don't speak to him when I have problems with injury or not playing.
"That is for you personally and you can tell the wife or your family. Sometime we discuss how games and training have gone. He is my best friend, my good friend and I am happy he is playing well now.What is the reason he didn't score before? I don't know, but at the moment he is the best striker in the Premier League."
Despite United and Berbatov arriving at the Reebok on Sunday as the top flight's premier unbeaten team, Petrov believes Owen Coyle's side can cause an upset.
"For everyone it's good to play against one of the best teams in the world," Petrov told ESPNsoccernet. "Of course, we want to beat them because it is not impossible, anything can happen in football - we are not scared and we won't go out on the pitch to lose the game. We will go out there and try to play football against one of the best teams and of course we have the possibility of winning the game."
Martin Petrov was speaking on behalf of Bolton's principal sponsor 188BET. The In-Play betting specialists will be offering a huge selection of markets with fantastic odds before and during Bolton's game against Manchester United. Go to www.188BET.com today and back Petrov to score first at 14/1 and then make sure you claim your free £25 bet.