IBF, IBO, WBA, WBO heavyweight champion Andy Ruiz is preparing for every version of Anthony Joshua.
The two fighters will collide in a rematch on December 7th in Saudi Arabia.
Ruiz pulled off a massive upset back in June, when he dropped Joshua four times to secure a seventh round stoppage at Madison Square Garden in New York City.
As he prepares for the possibility of getting revenge, Joshua has made adjustments in his training and with his body.
Joshua appears to have slimmed down, after numerous criticisms that he was packing too much muscle.
A lot of experts believe Joshua will user a lot more movement in the rematch, while keeping Ruiz at a distance.
Ruiz expects that possibility as well, and he's getting ready for that version of Joshua.
"We've got sparring partners running around and being slick," Ruiz told Sky Sports.
"A lot of people came to me and said that they wanted to help, like Michael Hunter. The only thing I'm doing differently is sparring. I've got a lot of different sparring partners in case he tries to switch his style up - in case he tries to box, or keep me away with the jab. We're practicing.
"I've had an almost three-month camp for this fight. We've got more things done. We've practiced what AJ is going to do."
Ruiz explained that he's still as hungry as ever, in preparing to retain his world titles.
"No-one said it's going to be easy. It's never easy. The hardest part is training, getting up in the morning, going for a run, going to the gym. The easiest part is going to perform," Ruiz said.
"Of course it will be hard but as long as you have the motivation to win, to conquer something bigger than I already did, then it gives you the advantage to pursue other dreams."