World heavyweight boxing champion Vitali Klitschko says Dereck Chisora will pose a big threat but he will knock the Briton out.
Chisora will take on the WBC champion in Munich mid next month.
At a news conference in London Chisora predicted he would fell drop Klitschko in the eighth round and revive interest in a division dominated by the 'boring' brothers.
Chisora warned Klitschko not to 'chicken out' like younger brother Vladimir, the WBA, IBF, WBO and IBO heavyweight champion who has twice pulled out of scheduled title bouts with him due to injury.
Vitali says he'll knock Chisora down in the sixth round .
But he adds he chose to take on Chisora because he is hungry and motivated and it will be a big fight.