Najee Lopez continues to be a knockout every time out. The unbeaten cruiserweight from Ellenwood, Georgia turned away his most established foe to date, stopping Jeysson Monroy in the third round of their preliminary bout Friday evening on ProBox TV from Osceola Heritage Park in Kissimmee, Florida.

Monroy (1-1, 1KO) was floored twice in round two but it was internal bleeding in his right eye that forced the stoppage. Lopez (5-0, 5KOs) was well in control to that point, putting in body work early against Monroy, a 2012 Olympian for Colombia who has participated in several combat sports mediums before returning to boxing last summer.

Lopez was poised in the opening round before turning up the heat. A straight right hand left Monroy crumpled in the final minute of the round. The 37-year-old Colombian beat the count but was back on the canvas near the end of the round. Monroy made it to the bell, only to suffer additional damage in round three. An up-jab by Lopez froze Monroy in place, complaining of compromised vision. The ringside physician examined him before ordering the referee to stop the contest.

Older brother Hakim Lopez had a more grueling affair, going all eight rounds in a unanimous decision win over Cruse Stewart in their battle of unbeaten super middleweights. Scores were 79-73 on all three cards in favor of Lopez in a fight that saw both boxers extended beyond the sixth round for the first time.

Lopez scored three straight knockouts heading into the evening, though all versus substandard opposition. Minnesota’s Stewart (8-1, 6KOs) was a step up in class, making things uncomfortable against the Ellenwood, Georgia product, but was outworked in too many rounds to make an impact on the scorecards.

Jan Paul Rivera has yet to see the second round of a pro bout. The 21-year-old boxer from Ponce, Puerto Rico made quick work of Los Angeles’ Cesar Martinez, scoring a first-round knockout in their featherweight bout.

Martinez (4-7-2, 1KOs) was trapped along the ropes, clipped by a right hand that left him open for an ensuing volley. A final straight right by Rivera produced the bout’s lone knockdown, with referee Samuel Burgos stopping the fight without a count at 2:13 of round one.

Rivera—who has three first-round knockouts since turning pro in March—and the Lopez brothers are managed by Tim VanNewhouse.

Jaycob Gomez Zayas (5-0, 4KOs) was forced to go the distance for the first time in his young career, setting for a six-round virtual shutout of Brazil's Marcello Williams (3-14, 0KOs). Scores were 60-54, 59-55 and 59-55 in favor of Gomez in their featherweight contest, which also marked the first fight to extend beyond the third round for the 20-year-old southpaw from Caguas, Puerto Rico. 

Trinidad Vargas was brief and effective in his pro debut. The 19-year-old former amateur standout from Grand Prairie, Texas made quick work of Josh Aarons, scoring a first-round knockout. Vargas floored Aarons late in the round, the sequence ultimately producing a stoppage at 2:31 of round one in their junior bantamweight bout.

Vargas boxed in the opening moments of his first pro fight before sensing that he could hurt Aarons (0-3, 0KOs), a winless fighter from Williamsport, Pennsylvania. Aarons failed to protect himself after getting clipped with a right hand to the temple, complaining to referee Emil Lombardo that he was hit behind the head. Vargas (1-0, 1KOs) closed the show, landing a pair of left hooks to produce the bout’s lone knockdown.

Aarons attempted to rise, falling face first to the canvas before staggering to his feet. He was unable to convince the referee that he could continue, prompting an immediate stoppage.

Vargas signed with David McWater’s Split-T Management last September after going 198-12 in the amateurs. The boxer’s first name comes as a tribute to Hall-of-Fame former three-division champion Felix ‘Tito’ Trinidad.

Headlining the show, Jonathan ‘Bomba’ Gonzalez (25-3-1, 14KOs) attempts the first defense of his WBO junior flyweight title against Mark Anthony Barriga (11-1, 2KOs), a former title challenger from the Philippines.

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox