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Jeison Rosario (20-1-1, 14 KOs) scored a huge upset on Saturday night over Julian ‘JRock’ Williams (27-2-1, 16 KOs) to win the WBA and IBF junior middleweight titles via fifth-round stoppage.
Williams, who had been considered by many as the kingpin of the 154-pound division, came into the fight as a huge favorite over the unheralded Rosario as the hometown hero in Philadelphia in the Premier Boxing Champions main event.
Rosario however, had other ideas as he showed a strong chin and willingness to trade against the defending champion.
After Williams controlled the pace in the first round with overhand rights, Rosario opened up a cut over Williams’s left eyelid from a jab that created problems from then on out. Rosario punctuated that second round with a two-punch combination that appeared to stun Williams.
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Then in the fifth round, Rosario stunned Williams with a right hand and followed it up with a flurry of punches that wobbled Williams, ultimately going down, albeit from the assistance of a push – it would not be called an official knockdown.
Williams took his time getting to his feet, as it was clear he was in a bad way. After finally getting up, Rosario unloaded with combinations along the ropes, prompting referee Benji Esteves to wave it off.
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