Tyson Fury says there is more to come from him after he beat Wladimir Klitschko to become the WBA, IBF and WBO heavyweight champion of the world.
The 27-year-old Briton outpointed the 39-year-old Ukrainian in Dusseldorf, Germany to bring his nine-year reign to an end.
"I think you have seen 65% of what I am capable of," the self-styled 'Gypsy King' told Sky Sports News.
"That wasn't as good as I can do. I can go up another level."
The Manchester fighter insisted he would beat Klitschko again if the former champion takes up the option of a rematch - and would be happy for it to be in Germany.
"If he had 10 years to train, the result would be the same next time," Fury said. "I think he will take the rematch, but who knows when he gets home and has time to think about it.
"It doesn't really matter to me where I fight. Japan, Turkey, Azerbaijan, America - wherever it has to be. I'd like to come back to Germany again to fight Wlad. I enjoyed it here and I got a great reception from the German fans."
He added. "I might be allowed a voluntary defence [before a potential rematch with Klitschko] and I would like to have that back in England, probably in Manchester. It would be great to bring the titles back."