Alexander Povetkin has started work to "neutralise" DIllian Whyte's most threatening punch.
The heavyweights collide in a high-stakes rematch on November 21, live on Sky Sports Box Office, after Povetkin sent Whyte crashing to a knockout defeat earlier this summer.
Povetkin was twice knocked to the floor before completing a come-from-behind victory but his preparations are underway to avoid being caught again.
"Everything is going according to plan, we have started sparring work," said his trainer Ivan Kirpa.
"We are working on a technical solution to neutralise Whyte's short left hook - obviously this is a technique he always does in every fight.
"The team is in a good working mood. We treat revenge with full dedication and understanding of everything that happens."
Povetkin's promoter Andriy Ryabinskiy denied that the Russian heavyweight was on the verge of being pulled out of the fight after twice being floored.
"It's nothing more than just rumours," Ryabinskiy told Sky Sports.
"The fourth round wasn't easy, it made us worry, but Sasha felt good, he was not particularly shocked. I think there were usual questions after the knockdown: 'Are you all right? Shall we continue the fight?'"
Whyte told Sky Sports: "I was controlling the fight, I was dropping him with punches that weren't even landing properly.
"I need to be more patient, more together, more switched on, more professional and pick my shots better.
"If I hit him with one of my punches properly, I'm very heavy handed, I can hit hard and if I connect properly he won't be getting up for sure!"
The race to fight Tyson Fury
Povetkin became the WBC mandatory challenger to Tyson Fury's world championship and will defend that status in the rematch with Whyte.
Whyte told Sky Sports about targeting Fury next year: "It was a slip up but we are about to sort it out. After I get past Povetkin, everything should still be back on course."
Fury has already agreed to two fights with IBF, WBA and WBO champion Anthony Joshua in 2021 to decide an undisputed ruler of the division.
But his next fight is up in the air - Fury has claimed that a third meeting with Deontay Wilder, targeted for December, is no longer happening because the American wanted to push it back into next year.
Fury insists he will fight in the UK before the end of 2020. He tweeted: "The Gypsy King is coming home. See you all in December."
Oscar Rivas, whose only defeat came against Whyte, is the highest-ranked available contender in the WBC rankings.
"Oscar is fit, available, ranked No 8 by the WBC and would gladly take the challenge," his co-promoter Yvon Michel told Sky Sports.
"Now for December I believe Oscar would be the best and the logical choice for Fury in his first title defence.
"We know Fury loves challenges and fights for the fans. Fury has written the best story of all for a fighter who became a heavyweight champion of the world and I am sure he is aware of Rivas' story.
"Rivas would be the best challenge and a fan-friendly fight.
"Oscar is in training and was supposed to fight on December 19 as co-feature on the Fury vs Wilder fight."
Fury's trainer Sugarhill Steward exclusively told Sky Sports: "Tyson and myself agree that another fight in 2020 makes sense, in sticking with the original plan to fight this year, period.
"I am really excited to see Tyson in the ring again to once again watch him grow into a fighter which the world anticipates viewing his future bouts henceforth in his career."