"I know I’m tough,” said Zepeda. “I didn’t know how tough I was.” (Mikey Williams/Top Rank)

In a Fight of the Year candidate streamed live Saturday night on ESPN+ from the MGM Grand in Las Vegas, Nevada, two-time world challenger Jose Zepeda (33-2, 26 KOs), the hard hitting southpaw from Long Beach, California, flattened Ivan Baranchyk, the former IBF junior welterweight champion from Miami by way of Amursk, Russia, at 2:50 of round five in a scheduled 10-rounder.

Fighting out of the red corner in black trunks with yellow trim, Zepeda was supposed to be the boxer, whereas Baranchyk, fighting out of the blue corner in black trunks trimmed in green, was supposed to be the puncher. But when the opening bell sounded, both men discarded facile descriptions to engage in an all-out war in which there were eight knockdowns.

Baranchyk set the tone by dropping Zepeda twice in the first round.

The fighters traded knockdowns in the second, with Zepeda drawing first blood from a cut over Baranchyk’s left eye.

Baranchyk, whose ring moniker is The Beast, went down in rounds three and four.

Zepeda was the first man to go down in the fifth, before he delivered a knockout for the ages that left Baranchyk on the canvas for five dispiriting minutes. The exhilaration of the fight had given way to concern for Baranchyk’s health. But he was eventually lifted onto a stool and made it out of the ring with assistance and taken to the hospital.

Timothy Bradley was handling the blow-by-blow and had flashbacks of the most brutal fight of his career.

“It brought me back to the Provodnikov fight,” he said. “Your soul is on display every time you get in the ring.

“It’s the severity of the sport. This is a brutal, brutal sport, man. I’m glad I got out when I did,” before adding, “He’ll (Baranchyk) never be the same fighter. A piece of him was left in the ring tonight. He’ll never get it back.”

After the fight, Zepeda said, “Boxing is hard. It’s no easy game. You have to give it 100 percent because it’s probably the hardest sport.

“I doubt myself too much. I’m a fighter who only has 16 amateur fights, so I always doubt myself.

“I know I’m tough. I didn’t know how tough I was. It was the first time in a fight like this. It was a learning experience.”