Former light heavyweight/cruiserweight champion Tomasz Adamek has vowed to succeed where David Haye failed and dethrone one of the Klitschko brothers in his fight with Vitali in Wroclaw on Saturday night.

Adamek challenges the elder Klitschko for his WBC heavyweight title in the biggest fight in Polish boxing history in the new 42,000 capacity Miejski soccer stadium.

Adamek, who like Haye moved up to the heavyweight division after forging a world-class career at a lower weight, has nothing but scorn for Haye's dismal attempt to dethrone Wladimir Klitschko.

Adamek said: "My opinion is if someone speaks too much you have to go to the ring and give a good show. But he (Haye) spoke too much, then he came to the ring and did not give a good show or try to win.

"I'm quicker than Vitali and I am going to kill him with my speed. Speed is power and it is going to be everything in this fight. I am not afraid to go in the ring to fight such a big guy."

Since moving to heavyweight in 2009 Adamek has beaten a number of credible contenders including Chris Arreola and former title challengers Andrew Golota and Michael Grant.

But the 40-year-old Klitschko, whose camp continue to leave open the possibility of fighting Haye in the future, believes the natural weight disparity will be too great for Adamek to breach.

Lack of action could be Klitschko's greatest threat. Since outpointing Shannon Briggs in October 2010 he has fought just one round against Odlanier Solis, who was forced out with a serious leg injury.

Klitschko said: "You have to be born as a heavyweight. Adamek has only grown into the division by eating like a heavyweight. There will be no questions afterwards about who won the battle."