Tim Tszyu beat up Jeff Horn in their Australian grudge match until Horn’s trainer, Glenn Rushton, had seen enough Wednesday night.

The younger, stronger Tszyu battered the former WBO welterweight champion for almost eight entire rounds, before stopping his awkward, rough opponent after the eighth round at Queensland Country Bank Stadium in Townsville, Australia. Rushton instructed referee Phil Austin to stop their scheduled 10-round junior middleweight match with a beaten, exhausted Horn sitting on his stool.

Sydney’s Tszyu remained unbeaten (16-0, 12 KOs) and moved closer to a shot at WBO junior middleweight champion Patrick Teixeira.

“All respect to Jeff,” Tszyu said. “He’s achieved so much. He’s given Australia this platform. It’s an honor to sell out an event like this stadium, with another fellow Australian. All respect to Jeff again. He was a tough competitor. But look, this is a young man’s sport and I was better this night.

“I said, ‘Give me competition, someone that could test me, and, you know, it’s sink or swim.’ And I’m not gonna sink. I’m here to swim.”

The 32-year-old Horn (20-3-1, 13 KOs), who’s most known for his controversial upset of Manny Pacquiao three years ago, slipped to 2-3 in his past five fights and lost by technical knockout for the third time as a pro. The Brisbane native moved back down to the junior middleweight division to fight Tszyu after two straight fights against Australia’s Michael Zerafa at the middleweight limit of 160 pounds.

“Look, Tim was young, hungry,” Horn said. “He’s an absolute champion, so I can’t put anything past him. He’s an absolute legend, so hopefully all of Australia can support him now. He now is the number one [boxer] in Australia. He wasn’t before this. He was saying he was, but he certainly earned it now. And he’s an absolute champion, and he can fly that flag very proudly for Australia.”

In the biggest fight of his three-year pro career, the 25-year-old Tszyu simply overwhelmed Horn with his activity, pressure and strength.

“He’s very good,” Horn said. “Look, he was on his game tonight and I wasn’t probably on my game. That was all credit to Tim as well. He was out-boxing me out there, and I guess he’s got that young blood. Not that I’m old. I’m not gonna say I’m old. Everyone’s saying I’m old, but I’m not. But yeah, Tim’s got that hunger about him.”

Facing Horn was considered a step up for Tszyu, even though Horn was stopped in the ninth round two fights ago by Zerafa last August 31 at Bendigo Stadium in Bendigo, Australia. Horn came back to defeat Zerafa (27-4, 16 KOs) by 10-round majority decision in their immediate rematch December 18 at Brisbane Convention & Exhibition Centre in South Brisbane.

Horn’s opponent, the son of the legendary Kostya Tszyu, knocked Horn to the canvas twice, once apiece in the third and sixth rounds.

Tszyu’s left to the body affected Horn 1:10 into the eighth round. Horn grazed Tszyu with a right uppercut just before the midway point of the eighth, but the former champ mostly missed wildly with his punches in that round.

Tszyu nailed Horn with a right to the side of his head 20 seconds into the seventh round. Austin warned Horn for a low blow with 1:42 remaining in the seventh.

A right hand by Tszyu landed flush with just under 30 seconds to go in the seventh.

Horn took a knee with 51 seconds on the clock in the sixth round after absorbing a left to the body. He caught his breath and fended off Tszyu to make it to the end of another round.

Austin admonished Horn for hitting Tszyu on the back of his head a few seconds into the fifth round. He threatened to take a point from Horn if he kept fouling.

Tszyu staggered Horn with a left hook just after the halfway point of the fifth round. A fatigued Horn held and wrestled his way through much of the remainder of the fifth round.

Tszyu blasted Horn with a right uppercut at the midway mark of the fourth round. He made Horn move away from him after landing another right hand shortly thereafter.

Horn, bleeding from his nose, landed a left hook just before the fourth round ended.

Tszyu flung Horn to the canvas with 1:45 left I the third round and again about 15 seconds later. Tszyu buzzed Horn with a right hand when the action resumed and Horn held on to regain his senses.

A left hook inside by Tszyu sent Horn to the canvas with 23 seconds remaining in the third round. Horn got up quickly and made it to the end of the round.

Horn and Tszyu spent much of the first minute of the second round wrestling and fouling one another. Austin called for a break with 1:47 remaining in the second round to warn them for their tactics.

Tszyu landed a short, right uppercut with about 40 seconds to go in the second round. He followed with a right to the side of Horn’s head several seconds later.

Horn lunged in and landed two left hands less than 30 seconds into the fight. Horn missed wildly with a right hand later in the opening round, which led to Tszyu hitting him with a straight right hand that backed Horn into the ropes.

Tszyu hit Horn with a straight right hand with about 1:15 to go in the first round that left Horn holding him.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.