Light-middleweight boxer Jason Rushton was rushed to hospital after suffering brain injury in a fight on Friday night.
The fight between the Doncaster boxer and Brian Rose was stopped with just one second of the tenth round remaining.
Mr Rushton was taken to hospital after leaving the ring and collapsing in the backstage area.
He was in a drug-induced coma in hospital on Saturday after being operated on to relieve pressure and bleeding on his brain.
Kevin McIntyre was in another fight at the same time and venue, but the second round was abandoned when Rushton was injured.
Mr McIntyre told the Sunday Mail: "This make you realise there are more important things than sport. I desperately hope Jason pulls through because he is a top lad."
According to the American Association of Neurological Surgeons, over time, professional boxers can suffer permanent brain damage. The force of a professional boxer's fist is equivalent to being hit with a 13 pound (5.9kg) bowling ball travelling 20 miles per hour.
News from Serious Law, specialist brain injury solicitors