Two American former world champions have raised concerns about Errol Spence Jr’s comeback against Tim Tszyu, warning the boxing superstar might be heading for heartbreak in Australia.

Just five weeks out from the blockbuster showdown in Sydney, Sergio Mora and Shane Mosley have both questioned whether Spence can return at an elite level against a dangerous opponent in Tszyu.

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The concerns come as Spence prepares for his first fight since being dominated by Terence Crawford in July 2023, with the former welterweight king returning straight into a showdown against the Aussie star without so much as a tune-up fight.

Mora, who has followed Spence’s career closely as a fighter, commentator and analyst, delivered a particularly grim assessment.

“He’s doing it for money,” Mora said on Boxing with Mannix and Mora.

“He’s doing it for the payday, he’s doing it because he’s been inactive for three years.

“This man has endured a horrendous car accident, flipping his Ferrari over that should have killed him, he escaped that.

“Then a horrendous beat down put on him by Crawford, and then the lifestyle that he lives outside the ring hasn’t been the cleanest…”

While Mora stressed that Spence was one of the best fighters of his generation and a future Hall of Famer, he believes the American is no longer the same man who once ruled the welterweight division.

“He’s not that guy anymore,” Mora said.

One of the biggest warning signs, according to the former WBC champion, is the way Spence now talks about life beyond boxing.

“That’s when you know they are not thinking about boxing,” he said.

“They are not thinking about legacy. They are not thinking about putting their health on the line anymore, because they’ve been doing it too long, and they know they’re one punch away from being a vegetable.”

“It sounds harsh, but it’s the truth.”

Sergio Mora, Errol Spence and Shane MosleySource: FOX SPORTS

Veteran boxing scribe Chris Mannix agreed with some of Mora’s concerns, admitting he struggles to see a positive outcome for his countryman.

“The only question is how does he lose?” said Mannix.

“Does he get beat violently? Or is he competitive and it goes to a decision?”

Mora again doubled down on his belief that Spence is chasing one final payday – and warned it could come at a heavy cost.

“It’s not going to end well,” he said.

“You’re going to pay that price in blood…

“When you hear Errol Spence talk, he’s always talked slow, you know that old Southern way of talking, but he sounds punchy now. It’s concerning…

“I know he’s in the Hall of Fame. I just hope that he can give a speech, a clear speech in the Hall of Fame, instead of chasing the last payday and really getting seriously hurt.”

Another red flag for Mora is the style Spence has built his career around.

“I hate that earmuff defense. It’s bound to catch up to him, and if he fights Tszyu, it’s not going to be nice, man. I think he did so much for boxing as an Olympian and as a champion, and he’s given so many great fights against great names.

“You know, it’s going to be tragic for him to go up against Tim Tszyu and take a beating on foreign soil like that. I don’t want to see it. I wish him the best, though.”

Mora isn’t the only former world champion who has concerns.

Hall of Famer Shane Mosley has also questioned whether Spence can return to his best after the damage sustained in both his horror car crash and the Crawford defeat.

Appearing on the MillCity Boxing podcast, Mosley said the biggest unknown wasn’t what Spence could do offensively – but how he would respond when the punches started coming in his direction.

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“He’s strong hitting the bag and such, but what about receiving,” he asked.

“What about the receipts? How is the body going to take the receipts?

“We’ve seen how good he looks hitting, what about getting hit back?

“I don’t know. We’ll see.”

But not everyone is writing Spence off.

One man backing the former champ to defy the doubters is his old rival, former undisputed welterweight king Terence Crawford.

Despite handing Spence the lone defeat of his pro career in their blockbuster showdown three years ago, Crawford has repeatedly insisted his former foe remains a top fighter.

Last week, Spence sat down with Andre Ward for an in-depth interview in which he reflected on the Crawford loss, admitting his preparation for the fight was “trash”.

While some fans accused Spence of making excuses for the defeat, Crawford quickly moved to shut down that narrative and publicly threw his support behind the Texan.

Card confirmed for Tszyu v Spence Jnr | 00:52

Taking to X over the weekend, Crawford wrote: “Still wishing @ErrolSpenceJr the best in his upcoming fight. I see what yall trying to do, but it’s not going to work, not this time.”

Earlier this year, Crawford not only tipped Spence to beat Tszyu – he put his money where his mouth is, reportedly wagering $10,000 on the result.