“As of this moment, Charles Oliveira remains the UFC lightweight champion, but upon the start of the main event headliner tomorrow night he will vacate the 155-pound title,” the statement read.

“The fight will proceed as scheduled, but the championship will only be on the line for Gaethje. If Oliveira wins, he will be the No 1 contender for the vacant championship and will fight the next challenger for the title at a time and place to be determined.”

A Brazilian correspondent for TV Globo had tweeted after Oliveira missed that several UFC fighters reported the weight-check scale – which is available to athletes to weigh themselves during the week – was showing different readings to the official scale.

“Someone tried to change from pound to kg during the week and recalibrated the scale,” tweeted Eva Rodrigues.

That account appeared to be backed up by Oliveira’s countrywoman, Ariane Carnelossi, who will face Lupita Godinez on the prelims at Footprint Centre.

“Congrats to the ‘genius’ that messed with the fighters’ scale leaving it with a 0.5lb difference,” wrote strawweight Carnelossi. “We only found out when we were informed as we were coming down to check our official weight. Luckily I was under so that didn’t hurt me.”

Norma Dumont, who faces Macy Chiasson in a featherweight bout this weekend, also missed by half a pound, but the scale did not appear to affect any other fighters on the card.

Oliveira gave his own account to TSN, claiming he made weight, and that “nothing changed, I am still the champion”.

“I’m just incredulous now. It’s just unbelievable what happened,” he said, via a translator. “It happened not just to me but to other UFC fighters. But that’s not going to change anything. We’re just going to keep pushing forward.

“We weighed in on the UFC scale [on Thursday night], go back to my room, nothing happened. We go back to it. It was a kilogram up, so how does that happen? The commission talks about the scale, they talk to other fighters. They don’t talk to us.

“Why does that continue to be an issue? Basically, it’s the same scale it was before. The commission talked to everybody else. It happened to other fighters, but we weren’t informed.”

The 32-year-old “Do Bronx” (32-8, 1 no contest) won the title after it was vacated by Khabib Nurmagomedov, with a second-round TKO of Michael Chandler in May 2021. He defended it with a third-round submission of former interim champ Dustin Poirier last December, racking up his 10th win in a row in the Octagon.

Oliveira has found huge success since moving up from featherweight, and has not missed the 155-pound mark before. He was given an hour to lose the extra half pound, and insisted he tried “everything” including working out, going to the sauna, and using a sauna blanket.

“Ever since we came up to the division, I made weight on a Thursday, so to me everything was fine,” he said. “We did everything we needed to do, that’s in our power to get that done, but the scale was not helping us.”

UFC 254: Khabib weigh-in official made ‘massive mistake’ says expert

The American “Highlight” Gaethe (23-3) seemed to disagree with that sentiment, however.

“Not my problem,” former interim champ Gaethje told TSN. “I was a little bit worried I wouldn’t have the chance to win the title, there was a little bit of confusion. He can make all the excuses he wants, but when you show up [to official weigh-ins] at 11 o’clock, s*** is obviously going south.”

Gaethje also cast doubt on Oliveira’s and Carnelossi’s claim that the weight-check scale was incorrectly calibrated.

“Both Brazilian,” Goethe posted on Twitter, with a laughing emoji. “I weighed the same on the digital [as] the official [scale].”

Former UFC lightweight Paul Felder – the last fighter to beat Oliveira, via second-round TKO in December 2017 – also appeared to have no sympathy for the champion.

“Wonder if he still wants to fight at 145. I have nothing against the champ. But this is a disgrace. And I honestly feel most for Justin. What an absolute let down for everyone in the division,” Felder wrote on Twitter.

A statement provided to MMA Junkie by the Arizona Boxing & MMA Commission seemingly put any blame for a mix-up with the weigh-ins on the UFC.

“Promoters are allowed to use the scale of their choice for official weigh-ins, as long as it has been deemed appropriately calibrated by Arizona Boxing & MMA Commission staff,” the statement read.

“Staff reviewed the official weigh-in scale to ensure proper calibration and found no issues prior to and during the official weigh-in. Any scales used for any purpose other than official weigh-ins (such as those that may be used for fighters to unofficially test their weight) are not calibrated or inspected by Commission staff as they are typically provided iced by the promoter.”