The final fight of the UFC’s first 25 years might have provided its most remarkable knockout.

Yair Rodriguez capped an outstanding main event with without a doubt the Knockout of the Year and perhaps the greatest knockout in UFC history.

With about five seconds left in a breathtaking battle that featured mixed martial arts striking at its finest, Rodriguez ducked under a left hand from “The Korean Zombie,” aka Chan Sung Jung.

When he came up, Rodriguez threw a right elbow that caught Jung square in the mouth. Jung went down and was clearly out. The only question was whether the KO came before or after the final bell.

It turned out it was with one second left — at 4:59 of the fifth round — to give Rodriguez an astounding victory in the main event of the UFC’s 25th anniversary card Saturday at the Pepsi Center in Denver. The fact that Rodriguez injured his foot in the first round made it all that more shocking. He said he thought he may have broken it when he kicked Jung on the knee.

Rodriguez, who took the fight on just two weeks notice, never slowed and battled fiercely from start to finish despite the swollen and painful foot.

Both men landed all manner of devastating strikes throughout, but each kept coming forward. Jung was ahead on two of the three judges’ cards before the final round so Rodriguez likely needed the strong finish to win. Sal D’Amato and Derek Cleary had Jung up 39-37 through four rounds, while Mark Van Tine had it even, 38-38. Yahoo Sports had it 39-37 for Jung, as well.

The scorecards didn’t matter, though, as Rodriguez almost guaranteed he’ll be viewed on highlight reels for as long as the UFC exists.

Jung went down and didn’t move for several minutes after the elbow. Rodriguez also hit the canvas in exhaustion and lay there even as his coaches attempted to pull him to his feet to celebrate with him.

It was a dramatic turn of events for Rodriguez, who was stopped by Frankie Edgar at UFC 211 18 months ago and then was cut by the UFC while also fighting personal problems.

But he was on top of his game — as was Jung — in this one. He might have knocked a lesser opponent out far earlier in the night, but Jung didn’t just take them, he answered with blistering shots of his own. Both men were covered in blood as the final seconds counted down.

“I know the title shot is going to be there eventually,” Rodriguez said. “The only thing I care about from now on is being happy every moment that I have. Being able to do what I love in the biggest company in the world is something I appreciate. Thank you so much.”

The pain of the last 18 months may not have been forgotten but Rodriguez will be remembered for as long as the UFC puts on fights after that unbelievable knockout. Jung had managed to avoid all manner of dangerous strikes from Rodriguez, but he walked right into the elbow that he never saw coming.

It’s that kind of finish which made the UFC so popular with fans and helped it grow so big so quickly.

It could have been Jung who scored it, given his ability to weather the storm and come back and punish Rodriguez. But Rodriguez first caught the UFC’s eyes with his dynamic and unconventional striking. He showed great heart and perseverance Saturday, and the poise to remain calm amid a great storm.

That he was able to even think of throwing that elbow, let alone landing it, was amazing. The fact it connected and scored the latest KO finish in UFC history made it one for the books.

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