LAS VEGAS (KLAS) — Daniel Corona was in one of the first fights of the night. His Sigma Alpha Epsilon fraternity brother Nathan Valencia, was in the last.

Now Corona is speaking out in an exclusive interview with NewsNation affiliate KLAS about the boxing night that ended with Valencia collapsed in the ring at the Sahara Event Center. He died from head injuries four days after the match.

Corona remembers as the event got started, his fight didn’t go smoothly. There were warning signs from the start.

He’s sharing his story so young people like him understand just how precious life is, along with a message for all of us: Don’t take life for granted.

In this case, Corona said the warning signs were there. But no one expected there would be a fatal consequence.

“Nathan was a good person and he didn’t deserve any of this,” he said.

Nathan Valencia is seen in video of the fight wearing red headgear as he participates in a fraternity boxing match on Nov. 19. The 20-year-old UNLV student collapsed after his fight.

Daniel Corona said he held Valencia’s hand in the ring.

“I told him, you’re gonna be OK, man. I told him you’re gonna be OK,” Corona said. “Just keep pushing through it. I thought he was gonna be OK.”

Valencia died four days later from head injuries.

Corona, 22, said he and Valencia trained together for about a month to participate in the charity event held by Kappa Sigma.

Valencia’s match was the last one, while Corona’s was earlier.

“I felt like I was fighting in a backyard … backyard fight,” he said.

He recalls no direction and no explanation of the rules.

“It just felt unprofessional,” Corona said.

His headgear was a problem. It had to be adjusted during his fight several times.

“I remember my headgear would cover one of my eyes while fighting,” Corona said. “And I had gloves so I can’t fix it.”

He also recalls running out of steam.

“It kind of felt like when you’re in a roller coaster and your head is like just going all over the place. That’s kind of how it felt when I got hit,” Corona said. He lost his fight.

Valencia’s parents say they believe the referee at the event was not a professional. Video obtained by NewsNation affiliate KLAS’ I-Team investigative unit appears to show the referee drinking alcohol.

“The referee didn’t know what he was doing,” Corona said.

The event wasn’t what he and Valencia thought they were signing up for.

“We felt it was gonna be actual professional referees,” Corona said. “We felt like there was gonna be medical standby.”

According to a 911 call obtained by the I-Team, no paramedics were on standby and there was confusion after Valencia collapsed.

A voice on the call says, “We have nurses here, but we need like real medical.”

Corona said there were nursing students who tried to help.

“Everyone was just trying to help. Everyone didn’t know how to help,” he said.

The Nevada State Athletic Commission, UNLV and Kappa Sigma say they are investigating the incident.

Corona said he believes the university and the fraternity should be held accountable.

“They took that responsibility when they decided to do a fight night,” he said.

Corona said he was given 12-ounce boxing gloves.

When shown video of the fight, Hall of Fame boxing referee Richard Steele’s first question was what size gloves were used.

He said they should be 16 ounces for amateurs so there is more cushion. It can really make a difference for punches to the head.

Corona said he is in the process of getting checked to make sure he doesn’t have injuries from his fight. He has been referred to a psychologist because of the traumatizing experience.