World heavyweight champion, Deontay Wilder, says Tyson Fury has made a "mistake by tinkering with his training for their February 22 rematch.
Fury, 31, parted company with trainer, Ben Davison, in December and is working with Javan 'SugarHill' Steward.
The Briton has since said he intends on knocking out Wilder despite believing he won when he used a more cautious strategy when the pair drew in 2018.
"We haven't seen his power displayed like he's talking about, said Wilder.
"It hasn't been continuous like mine. I think he has pillows as fists. That's what I felt in our last fight.
"With the strategies that he's talking about, I don't really know how to take it. I don't know if he's trying to throw me off my game by saying he's going to knock me out.
"When you fight someone like me, it's a mistake to tinker around with your training camp. I'm unpredictable in that ring.
"When you have too many opinions and too many people who think they have the remedy, it usually backfires.
Former world middleweight champion, Andy Lee, is part of Fury's team for the rematch and has said he expects his fighter to have "more authority in his punches than when he twice rose from the canvas to earn a draw in Los Angeles.
Many of those ringside for the first contest believed Fury had won. He was adamant he had done enough to take the WBC world title from Wilder, but this time says he will deliver a stoppage within two rounds.
In addition to changes to his team and tactics, Fury is expected to weigh in heavier. He told BBC Radio 5 Live he weighed 269 pounds - up from the 256 pounds he weighed against Wilder last time and the 254 pounds he scaled against Otto Wallin in September.
After the win over Wallin, Fury's dad said his son looked as "weak as a kitten.
Alabama's Wilder boasts 42 wins - 41 via knockout - from his 43 bouts, while Fury has 20 stoppage wins from his 29 victories.
Fury said: "How do you beat a massive puncher? You have to back him up. He gets massive leverage in those long arms while coming forward. I have to put him on the back foot and make him absorb some of my power.
"We're giant heavyweights. I've had 20 knockouts, so I'm very capable of knocking people out. When you underestimate someone else's power, you usually end up unstuck.
"Whether I'm a great puncher or not, I don't believe anybody else can match me with heart and determination.