But there's just one problem: Johnson can't make weight at middleweight, either. Johnson came in at 197 pounds.
Just before the UFC 142 weigh-ins on Friday in Rio de Janeiro, UFC President Dana White announced that Johnson is over the 185-pound limit and won't be able to get down, and so the fight is in jeopardy, although Belfort is expected to agree to fight Johnson anyway.
"Rumble Johnson is not on weight today. And when I say he's not on weight he's way off weight," White said.
So the UFC has essentially decided to turn this into a light heavyweight bout, but with an added condition: They'll have a second weigh-in on Saturday at which Johnson will have to make it under the light heavyweight limit of 205 pounds again. If Johnson can't make weight then, the fight is off.
"The stipulation is, Vitor does not want him to weigh more than 205 pounds by tomorrow at like 2 o'clock in the afternoon," White said. "So we'll see how this thing plays out. He'll weigh in today and have to weigh in tomorrow."
White made it clear that he's not happy with Johnson.
"As a fighter, you are a professional. You are contracted to come in at a certain weight. This is not the first time this has happened with Johnson. He moved up to 185 pounds so this wouldn't happen to him at 170 pounds, and here we are in the same position again. [Belfort] came in like a professional on weight, and Anthony Johnson comes in as a total unprofessional, way overweight."
White appeared angry enough on Friday that this might be Johnson's final fight in the UFC in any weight class.