In a massive blow to Australian boxing superstar Tim Tszyu, his long-awaited world title unification fight with undisputed champ Jermell Charlo has been ruled out.

Super welterweight champion Charlo (35-1-1) will instead move up two weight divisions to fight super middleweight undisputed champion Saul ‘Canelo’ Alvarez (59-2-2, 39 KOs).

Tszyu is the mandatory WBO challenger for Charlo’s crown, and a bout was expected to take place in Las Vegas in October – giving the Australian a chance to become the 10th undisputed champion in the four-belt era.

Meanwhile, 32-year-old Alvarez was set to fight 33-year-old Charlo’s twin Jermall, the WBC middleweight champ despite not fighting in two years due to personal issues.

But Tszyu was left blindsided by a last-minute swap as Charlo and Alvarez overnight announced they will face off on September 30 in Las Vegas.

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The fight will make history as the first time two fighters actively holding undisputed titles face off in the four-belt era.

It will attract huge interest from a global audience and deliver Charlo a significantly bigger payday than a bout with Tszyu.

Tszyu reacted to the shocking announcement by claiming Charlo was ‘ducking’ his mandatory world title fight with the Australian.

He wrote on Instagram: “Canelo ducks Benavidez. Charlo ducks Tszyu #Boxing.”

Alvarez has widely been accused of avoiding a bout with his own mandatory challenger David Benavidez, a two-time super middleweight champ. Alvarez reportedly turned down an offer worth around $45m USD to fight Benavidez.

Alvarez, who has won multiple world championships across four weight classes, defended his super middleweight titles with a decision win over John Ryder in Mexico in May.

Meanwhile Charlo has not fought since May 2022, when he knocked out Brian Castano in a world title rematch to claim all the belts at 154 pounds.

23-0 (17KOs) Tszyu had been slated to fight Charlo for undisputed world champion status earlier this year, but a serious hand issue for Charlo forced the fight to be postponed twice.

Tszyu has remained active while waiting for the champion to heal – a high-risk approach, given a loss could have seen him plummet down the rankings and lose his shot at the champ.

But Tszyu took on a significant challenge in Tony Harrison in March, the only man to have defeated Charlo, and came through in impressive fashion.

Then he went to another level in a first-round demolition of Mexican Carlos Ocampo in May.

“There’s no doubt I’m going to America, that’s the land I want to conquer,” Tszyu said after that impressive win retained his WBO interim light-middleweight title.

“I’m not satisfied with his interim belt – I want all four and I want the name Charlo on my resume. Let’s dance in October.”

But that anticipated October bout has now been scrapped, robbing Tszyu of his chance to unify the division.

Given there was a September 30 deadline for Charlo to negotiate his meeting with mandatory WBO challenger Tszyu, it appears likely that the WBO will strip Charlo’s belt and elevate Tszyu from interim to a full world champion.

The WBO is the organising body under the most pressure to act, and could potentially strip Charlo of his belt as early as today.

It would be a disappointing manner for Tszyu to finally achieve world domination.

Tszyu has also repeatedly stated he was chasing a Charlo fight for reputation – the chance to beat the standout in the division – rather than belts.

Tszyu’s next fight is unclear. One option is Bakhram Murtazaliev, the mandatory IBF challenger to Charlo, who could potentially inherit Charlo’s belt if the IBF also chooses to strip that belt.

The Australian had reportedly been close to a deal to fight the 21-0 Russian in March before Murazaliev was injured.