Mike Tyson weighed in at his lightest for 23 years for his exhibition bout against Roy Jones Jr on Saturday night.
Jones scaled 210lb - the heaviest of his career - before Tyson weighed 220lb, the lightest he has been since he took a chunk out of Evander Holyfield's ear in their 1997 rematch.
Jones' previous heaviest was 204lb for his clash with Eric Watkins in 2015.
After weighing in, he said cryptically: "I can't tell you how to do it, it's probably going to look wrong. If I try to tell you it's probably going to sound wrong. But it's going to turn out right, trust me."
And Tyson added: "I'm pitching punches and anything else is up to Roy.
"If I am running anywhere, I am running right at him."
In the co-main event, former NBA star Nate Robinson will make his professional debut against loudmouth YouTube star Jake Paul who fights for the second time.
Robinson said, rather loftily: "I just want to prove I'm the greatest athlete to ever walk this earth."
Paul, who beat fellow social media star AnEsonGib on his debut in January, said: "I love the sport, I'm made for this and to me it's an opportunity to prove people wrong.
"It's something I fell in love with, something I'm passionate about and something I'm good at and I'm going to take the world by storm.
"Nate's kids, if you're watching, don't watch the fight, I don't want t embarrass your dad in front of you. It's going to be bad, it's going to be bloody."