Coming into his fight with the previously unbeaten Bektemir Melikuziev on Saturday night, few gave American Gabriel Rosado much of a chance.Now entering the final stages of his boxing career, most observers felt that the 40-fight veteran had been selected to provide Uzbekistan's Melikuziev with victory over an established contender. Having lost two of his last three bouts, the former two-time super middleweight world title challenger was as big as 9-1 with the bookies to score a win over Melikuziev, winner of a silver medal at the 2016 Olympics.Big things are expected of the 25-year-old Melikuziev, who had won all seven of his professional bouts heading into this weekend's clash with Rosado.He was even scheduled to face former light heavyweight world champion Sergey Kovalev earlier this year - before injury took the hard-hitting Russian out of that contest.Saturday's bout at the Don Haskins Center in El Paso was supposed to be another stepping stone for Melikuziev towards regular involvement in those kinds of fights. However, Rosado had other ideas!Melikuziev began well in the first couple of rounds, flooring his 35-year-old foe in the first session. Everything was going according to the script for the former Olympian - until the mid-way point of the third round.Sensing that he needed a big shot to change the momentum of the fight, Rosado uncorked a massive right hand out of nowhere that completely separated Melikuziev from his senses.DAZN shared the crazy moment on its official Twitter account, which you can see here...

To his credit, Melikuziev tried bravely to get up, but he was clearly in no position to continue, floundering around the ring as he tried, in vain, to regain his feet.

The final seconds of the bout will be replayed for many years to come, with the finish definitely a contender for 'Knockout of the Year'. Fans on social media were buzzing after the shocking turn of events, as many fans praised Rosado's calmness under pressure.

"Displayed pure veteran tactics. Weathered the storm, stayed calm. Great shot," declared one tweet, per The Sun.

"Rosado ain’t read no script," exclaimed another.

After playing the role of spoiler this weekend, Rosado has resurrected his own career in emphatic style. World title opportunity number three might not be too far away for the experienced American.

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