Anthony Joshua expects to stop Tyson Fury within six rounds when the heavyweight rivals clash next year.
The two world champions, who hold all four belts between them, have agreed in principle to fight twice in 2021.
The bouts would determine the first undisputed champion since Lennox Lewis' reign ended 20 years ago.
Joshua must first overcome mandatory challenger Kubrat Pulev while Fury is due to take on Deontay Wilder for a third time later this year.
Assuming they come through unscathed, the Brits could touch gloves next summer.
And Joshua told Sky One: "I have a lot of respect for the man, he's a good family man and a good fighter, but on the other hand, I want to break his head.
"First six rounds, I think, well I know I'm going to take him out then.
"I have had a shorter career, so I'm fresher. I've been in the deep end longer so I can handle the pressure and I believe I'm going to take him out.
"Fury drew the first (fight with Wilder) and then rejigged his game plan and took Wilder out and schooled him really but I think I'm faster than Wilder anyway, call it what you want, I believe I'm better."
Joshua and Fury are expected to return to the ring for their respective final hurdles in December but the dates remain fluid due to the coronavirus crisis.
Their bid to crown an undisputed champion was accelerated last weekend when Dillian Whyte was knocked out by Alexander Pokvetin.
Victory for Whyte would have guaranteed him a shot at Fury or Wilder before the all-British clash, but he must now go back to the drawing board.
The Londoner will first have to rematch Povetkin and may then have to wait a further 12 months for his shot.
