Former light heavyweight world champion Adonis Stevenson was in a medically induced coma but was upgraded from critical condition to stable on Sunday, according to promoter Yvon Michel.

"The state of Adonis has gone from critical towards stable from (Saturday) to (Sunday), which is relatively good news. He is in controlled sedation to facilitate his recuperation," Michel wrote on Twitter. "His family, his (fiancée) Simone and Groupe Yvon Michel would like to thank the many people who have taken the time to send comforting messages. New information will be published as we get it. No other comments will be made until then."

Stevenson suffered a brain injury when he lost the light heavyweight world championship by 11th-round knockout to Oleksandr Gvozdyk on Saturday night at the Videotron Centre in Quebec City, after which he was taken to Enfant-Jesus Hospital in Quebec City.

Stevenson, 41, of Montreal, was eventually admitted in critical condition and placed in a medically induced coma, a method used to allow time for swelling on the brain to go down.

Stevenson, who was making the 10th title defense of his 5½-year title reign, was ahead on two of the scorecards, a surprisingly wide 98-92 and 96-94, with the third judge having it 95-95 when Gvozdyk (16-0, 13 KOs) stormed to the knockout. He landed eight unanswered punches, including a left hand and two crushing rights that badly hurt Stevenson (29-2-1, 24 KOs), who went down and slumped against one of the corner posts. Stevenson tried to get to all fours but fell partially onto the ring apron between the bottom two ropes as referee Michael Griffin waved off the fight at 2 minutes, 49 seconds.

Stevenson was able to eventually get to his feet and sit down on a stool to be examined by the ringside doctor and appeared alert until his condition deteriorated.

According to the Montreal Journal, Stevenson was in his dressing room discussing the fight with Michel and then went to shower. When he came out, he started to feel dizzy and had trouble standing, according to the newspaper. At that point, the doctor was called to examine Stevenson again and he decided to send him to the hospital. Stevenson lost consciousness in the ambulance on the way to the hospital, according to the newspaper.