Raoni Barcelos collapsing unconscious on the canvas during the UFC Vegas 121 main event against Raul Rosas Jr. left everyone deeply concerned. But while the Brazilian bantamweight eventually regained consciousness while under treatment at a hospital in Las Vegas, the exact reason behind his sudden collapse remained unclear. Now, his longtime mentor Glover Teixeira has provided an explanation of what may have happened.

In a conversation on the Overdogs Brazil podcast, former UFC light heavyweight champion turned coach, who was one of the cornermen for Barcelos, discussed the UFC veteran’s condition and revealed what he had been told by the doctors after the fight.

“It was different because it wasn’t a knockout,” Glover Teixeira said. “If it had been a knockout, we’re used to that. A fighter takes a shot, gets knocked out, okay, let’s take him to the hospital, all right. But this was something that happened out of nowhere, and we started thinking about all kinds of things. Could it have been his heart? Could it have been something neurological? They went in and ran the tests.

“There was some swelling in his brain, so it was a traumatic brain injury, and maybe that swelling caused him to black out. It was the body’s defense mechanism. ‘Let’s shut this down because this guy isn’t going to stop.’ His mind was stronger than his body, right? He didn’t want to give up.”

According to Teixeira, the collapse in the opening minutes of the fifth round may not have been caused by the apparent slam from Rosas Jr. that many initially thought contributed to Barcelos losing consciousness.

The former champion said that medical tests conducted at the hospital revealed Barcelos had swelling in his brain, which he described as a traumatic brain injury. For now, the exact medical diagnosis and cause of the swelling have yet to be publicly detailed by Barcelos’ medical team.

The 39-year-old’s own physician, Dr. Gustavo Medeiros, who monitored the fighter through his team in Las Vegas, previously described what happened as a “sudden illness” and said the Brazilian was not in any immediate danger.

However, a different doctor, Dr. Brian Sturrer on YouTube, ran an assessment of Barcelos’ condition and pointed out that the 22-6 fighter could have developed brain injuries as a result of the repeated shots he took to the head during the five-round war with Raul Rosas Jr.

Teixeira, who has mentored Barcelos since 2009, also revealed that he and Barcelos’ father, Laerte, initially wondered whether an accidental clash of heads could have caused the sudden collapse.

“Laerte is an extremely stoic guy, [saying] ‘Yeah, we have to see. I don’t know if it was an accidental headbutt that we didn’t see,’” Teixeira added. “It looked like it might have been an accidental headbutt and then he went down, but we didn’t know. And seeing him being taken out on a stretcher at that moment, man, it was the most desperate moment in MMA.

“I saw everyone’s faces, Hunter’s face, the concern. I was worried too, but I kept looking at everyone’s faces. You find yourself looking for the expression of the UFC doctor.”

For Alex Pereira’s coach, watching his longtime student lying unconscious on the canvas and being taken out on a stretcher was understandably difficult. Fortunately, Barcelos soon began showing signs of recovery while under treatment and was eventually able to reassure his supporters himself.

Raoni Barcelos addresses fans following scary UFC Vegas 121 collapse

Following the incident, the UFC confirmed that Barcelos had been transported to a Level 1 trauma center for further evaluation.

After spending hours under medical supervision, the 39-year-old regained consciousness and was able to communicate with those around him. He later addressed his fans from his hospital bed in a video shared on social media.

“I’m doing really well and undergoing all the exams here at the hospital,” Barcelos said. “This is just the hospital’s protocol, so I have to go through all of them. That’s it, guys. I want to thank everyone for all the prayers and all the kind messages. Please keep sending that positive energy.

“We move forward, on to the next one. I gave everything I had inside that cage. Like I said before, I was only leaving that cage if I was carried out, and that’s exactly how it happened. It wasn’t the way I wanted it to be. I wanted to become champion and leave with the victory, but God knows everything. So we move on to the next one.”

Days after the incident, Roani Barcelos was discharged from the hospital and reunited with his family. The UFC veteran again thanked everyone who had sent him messages of support by sharing a picture with his wife and young son.

Barcelos’ recovery is undoubtedly the most important development following the frightening incident. As for what caused his collapse and what it means for his fighting career, more information from his medical team will be needed before any conclusions can be drawn.

For now, the 39-year-old’s priority remains the same: recovering fully after one of the most frightening moments of his UFC career.