Tyson Fury says he'll get Vitali Klitschko out of retirement once he has 'flattened' younger brother Wladimir.
The British heavyweight challenger called the elder brother out on an intense The Gloves Are Off, starting the countdown to November 28, in Dusseldorf.
Fury believes the age difference will see him beat 39-year-old Wladimir and then prove his point by taking on Vitali, who is five years older.
"I'd beat both of them," Fury told The Gloves Are Off. "Give me a couple of weeks, I'd prepare for both of you [Wladimir], no problem.
"I am sure that once I've flattened you, your brother might come out of retirement and fight me as well.
"So who knows where this journey takes me? But first off it's Dusseldorf and Wladimir Klitschko. He's going to sleep."
The older Klitschko retired three years ago and is now concentrating on his political career but has beaten British heavyweight challengers, Danny Williams back in 2004, Herbie Hide and Dereck Chisora in his penultimate fight.
The younger of the two could match that on November 28 after out-pointing David Haye in Hamburg four-and-a-half years ago.
Fury though, is only 27 and is adamant that age will work against Klitschko, who is defending his WBA Super, WBO and IBF world heavyweight titles at the ESPRIT arena.
"They key factor here for me is your age," he told Wladimir. "My ability is going to make your age catch up with you. No matter how hard you train, how good you feel, you can't compete with young athletes.
"Just remember the age factor is the key to victory. That rhymes as well… the age factory is the key to victory.
"There is a saying that old people say: the mind is willing but the body isn't able.
"You are going to learn what a young man does to an old man and I don't have to be the best fighter in the world to beat an old man."