Adonis Stevenson, who reigned as light-heavyweight champion from 2013 until his 11th-round knockout loss to Ukrainian Oleksandr Gvozdyk on Saturday night in Quebec City, was hospitalized after the bout and remains in critical condition Sunday morning.

Stevenson’s promoter, Yvon Michel, reported on Twitter on Sunday that Stevenson, 41, is “currently under careful medical supervision of very competent doctors in a controlled environment.”

The Haitian-born Stevenson (29-2-1, 24 knockouts) was leading on two of three scorecards Saturday in making his 10th World Boxing Council title defense despite getting knocked down in the third round (which referee Michael Griffin ruled a slip) and taking some heavy shots throughout the bout.

The 31-year-old Gvozdyk (16-0, 13 KOs), a stablemate of lightweight champion Vasiliy Lomachenko and unified cruiserweight champion Oleksandr Usyk at the Oxnard-based Boxing Lab, showed no intimidation before Stevenson’s vaunted power and engaged in a competitive bout that judge Mike Ross had 95-95 after 10 rounds.


In the 11th, Gvozdyk swarmed and landed a hard right hand that snapped Stevenson’s head back and sent him reeling to a corner, where Gvozdyk finished him with a power punch that sent Stevenson crumpling to the canvas.

It’s unclear where Stevenson’s condition deteriorated from the time he left the ring, but brain swelling can occur several minutes following the trauma.

Michel originally reported around 11:30 p.m. PST – around five hours after the fight – that Stevenson was in intensive care.

“I just heard about Adonis at [the] hospital,” Gvozdyk manager Egis Klimas texted to the Los Angeles Times on Sunday morning. “We all pray and hope he will be OK.”


lance.pugmire@latimes.com

Twitter: @latimespugmire