Daniel Dubois of the United Kingdom felt “cheated out of victory” after losing his heavyweight world-title challenge to Ukrainian Oleksandr Usyk in front of 40,000 raucous fans in Poland.

Dubois, a massive underdog, knocked out the champion in a contentious fifth round. The referee deemed the shot, which appeared to hit on the belt line, a low blow as Usyk writhed in anguish on the ground.

Usyk, 36, regained control and downed Dubois, 25, with a flurry of blows in the eighth round at Wroclaw’s Tarczynski Arena, before the fight was stopped due to another knockdown in the ninth.

“I didn’t think that was a low blow, I thought it landed,” Dubois stated following the bout.

Frank Warren, his promoter, agreed, calling it a “complete home decision” while criticizing referee Luis Pabon and stating that he intends to appeal.

“I like Usyk, but he wasn’t fit to play and they gave him a few minutes to recover,” Warren continued.

Usyk took three minutes and 45 seconds to declare himself fit to restart – boxers are permitted five minutes when caught with a low blow, but the referee did not penalize a point from Dubois.

The former undisputed cruiserweight champion responded brilliantly near the end of the fifth round and reasserted his authority in rounds seven and eight as he successfully defended his WBA ‘Super’, IBF, and WBO belts for the second time.

He also kept his undefeated record alive by winning his 21st professional fight, keeping dreams of a blockbuster match with Tyson Fury alive.

“I’m ready to fight Tyson Fury,” Usyk declared.

“I’m feeling terrific. I am thankful for my teammates, my family, and my children. I adore you. I appreciate my country and the Ukrainian army. Thank you a lot.”

Fury, the WBC world champion, and Usyk had already failed to reach an agreement on a historic fight for all four heavyweight belts.