Tim Tszyu has been released from hospital, but his career remains in limbo following a second brutal beat-down in the US.

American “Towering Inferno” Sebastian Fundora boxed Tszyu into submission in their world-title rematch in Las Vegas.

Australia’s former WBO super-welterweight champion was taken straight to hospital after being unable to carry on after a ferocious seventh round at the MGM Grand’s iconic Garden Arena.

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Ironically, Tszyu looked to be turning the fight in that seventh round after being dropped in the opener by a savage straight left to the head from Fundora.

Despite being bloodied himself, Fundora caught Tszyu with a flurry of upper cuts in the final seconds of the seventh that shook the Australian before he told his corner he did not wish to continue.

Tszyu had been attempting to emulate his Hall of Fame dad Kostya as only the third father-son duo in boxing history to both win multiple world titles.

“Shattered for Tim, first and foremost. Shattered knowing how hard he worked for this and how bad he wanted it,” Tszyu’s promoter George Rose said.

“Very sad night at the office, but I’m glad that he’s walked out of the ring.”

Rose commended Fundora for putting on a masterclass in defence of his WBC strap.

“Best I’ve ever seen Fundora fight, hands down,” said the No Limit Boxing boss.

“I thought the strategy that they had coming in, how he fought long, he really used his length early. He was tremendous, a really good win for him and I don’t think anyone else in the division beats him now.”

The tallest world champion in all of boxing, standing at 197cm and boasting a massive reach advantage over his rivals, Fundora didn’t allow Tszyu to get to him without being exposed himself.

Still, Rose maintains Tszyu can climb the mountain again - if he wants to.

“First and foremost, he needs to just recover from this, go through your process of facing defeat,” Rose said.

“You’ve got to go through your moments with that, and then it’s a decision for him.

“He’s still, as far as talent and capability goes, very much a very capable fighter, a very talented fighter, and I still think that he still beats most of the guys in the division on his night.

“It’s just a decision up to him as to what he’s going to do, whether he gets back in the gym on Monday, whether he has a break, what he does.”

Rose insists it’s too early to speculate about whether or not the 30-year-old will fight on, having lost three of his past four bouts after going unbeaten in his first 24.

“In this sport, a loss is a long time that you’ve got to deal with that for,” said the former premiership-winning NRL prop.

“It’s not a one-week thing like most team sports where you can move on within a week.

“A lot’s got to happen on the back of it. Firstly, you’ve got to go medically.

“Then you’ve got to look at where the hunger’s at, and Tim’s one person you never can question his hunger or desire or the amount of application he puts in with his efforts in this sport. He rips in.

“He just fought for a world title at the MGM Grand so, while that’s a really cool thing, taking a loss is a tough thing.

“I know Tim’s still very talented, very capable, but it comes down to him. He’s the guy who’s got to put his life on the line in the ring.

“So the decision is on him, and I support him with whatever he chooses 100 per cent.

“If he wants to make another run for a world title, I’ll do everything in my power to make that happen.

“It’s his health first.”