Wladimir Klitschko taught Anthony Joshua the importance of good sparring partners and that has helped the world heavyweight champion get into tip-top shape ahead of his first bout in over a year against Kubrat Pulev.
Saturday will be the first defence of the 31-year-old's second reign as holder of the WBA, WBO, IBF and IBO belts which he won back with a points victory over Andy Ruiz Jr last December.
A June date had originally been pencilled in but the coronavirus pandemic forced it to be put back six months and it extended Joshua's time outside of the ring.
"If you don't concentrate and you look to what you've got in four or six months, you'll slip up and future huge fights will never materialise," McCracken said.
"It's the same for Tyson as well. He's got to make sure that if they eventually box that he stays unbeaten as well. It's very tough heavyweight boxing – they are always one punch away from disaster.
"But he's trained long and hard for this one. He's taken Pulev deadly serious, most days there's been two boxing sessions a day and he's enjoyed it.
"He's looking forward to the fight and is in a good mood, and that's really key when he comes out of a camp."
