Ukrainian coach Vladimir Zolotarev, the first trainer of the Klitschko brothers, revealed that they never held full-fledged sparring sessions with each other, and he explained the reason why.
— I understand the brothers often sparred together?
— No, they didn’t spar.
— Was it rare?
— Very rare. We didn’t even do sparring because their mother forbade it. She said, "They shouldn’t fight each other." They would often work together in drills, but rarely in sparring.
— Who looked more powerful during the sparring sessions? Or was that not the goal?
— No, that wasn’t the goal. It was just for speed, light punches. But they didn’t actually fight, Zolotarev said.