The imperious Tszyu, son of boxing legend Kostya, improved to 16-0 in Townsville on Wednesday (August 26) and quickly case his gaze towards a potential meeting with WBO light-middleweight king Patrick Teixeira.
Former WBO welterweight champion Horn, who defeated Manny Pacquiao in July 2017, was dropped twice before he retired on his stool ahead of round nine, succumbing to a third loss of his career.
The build-up to the fight was overshadowed by a claim that Tszyu had been training at a gym owned by one of the judges, while another was forced to apologise after it emerged he had tipped Tszyu to win.
The WBO refused to change the judges, but Tszyu ensured they were not needed.
After a scrappy start Tszyu found Horn’s chin with a powerful left uppercut in the third round and sent him to the canvas.
Horn managed to get back to his feet but his opponent remained in control, working the head and body effectively to grind away at the 32-year-old.
WBO global super welterweight champion Tszyu followed an excellent right with a body shot to send Horn down for a second time in round six but he continued to show patience and was rewarded at the end of the eighth.
In a post-fight interview, Tszyu said: “All respect to Jeff, he’s achieved so much. He’s given Australia this platform. This is a young man’s sport and I was better this night.
“I said, ‘Give me competition, someone who can test me.’ It was sink or swim and I’m not going to sink, I’m going to swim. I want the real world title strap around my waist soon.
“I’ll be back in the gym Monday and I’ll be training, because I know this is not the end, this is just the beginning and this motivates me to keep going.
“It was an honour to share the ring with Jeff.”
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