Sergey Kuzmin has been slammed for posting a sickening video of him knocking a sparring partner out cold.
The Russian heavyweight uploaded a video of himself brutally knocking out his sparring partner on social media.
He appears to land a devastating right hand which immediately flattens his sparring partner who lies motionless on the canvas before receiving medical attention from a coach.
Kuzmin, meanwhile, walks away to a corner before approaching the stricken boxer.
Needless to say, fans reacted angrily to Kuzmin sharing the video.