LAS VEGAS – Eumir Marcial seemed destined for an upset defeat Saturday on the non-televised portion of the Erickson Lubin-Sebastian Fundora undercard.

The Filipino southpaw, a 2020 Olympic bronze medalist promoted by Manny Pacquiao’s company, got up from three knockdowns overall in the first two rounds and scored a controversial fourth-round knockout of game underdog Isiah Hart. Marcial knocked Hart into the ropes with a left hand in the opening minute of the fourth round, which caused referee Raul Caiz Jr. to step between them to halt the action 47 seconds into the fourth round of a scheduled six-rounder.

Hart and his handlers understandably questioned the stoppage because, unlike Marcial, Hart had not been knocked down during their middleweight match.

Nevertheless, Marcial improved to 2-0 and recorded his first knockout in his first fight since December 2020. Hart, of Mays Landing, New Jersey, slipped to 6-3-1 (4 KOs).

Hart first floored Marcial during the first round. A stunned Marcial got up quickly and aggressively went after Hart during the second half of that opening round.

A fully recovered Marcial was winning the second round until Hart dropped him twice more, both times with straight right hands when a reckless Marcial was on the attack. A resilient Marcial reached his feet quickly after the second and third knockdowns as well.

The favored fighter then went after Hart as soon as the fourth round began. Hart tried to move away from him, but Marcial caught him with the aforementioned left hand that led to this debatable conclusion.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.