Antonio Mireles experienced a series of firsts in his latest victory.

The undefeated heavyweight survived a third-round knockdown to barely edge Patrick Mailata over six rounds. Judge Jerry Cantu (57-56) ruled in favor of Mailata, but was overruled by judges Dr. Lou Moret (57-56) and Steve Morrow (57-56) who scored the bout for Mireles in their ESPN-televised opener Saturday evening from Save Mart Arena in Fresno, California.

Mireles had never fought past the second round through six pro bouts. He’d also never faced anyone who posed a threat. All of that changed versus the hefty Mailata who has yet to be taken off his feet now through eight pro bouts.

The 6’9” Mireles fought largely behind his jab in the opening round, occasionally followed by a straight left with little power behind it. Mailata was far more selective in his approach but It proved effective late in round two. Mireles was directly in front of the squat Samoan, who worked his way inside and threw crisp right hands in the direction of the Iowa native.

Mailata struck gold late in round three. Mireles threw mostly arm punches to that point but was forced to drastically adjust his approach after hitting the deck. A right hand by Mailata left his unbeaten foe on unsteady legs. A pair of sweeping left hooks eventually forced him to the canvas in the closing seconds of the round.

To his credit, Mireles bit down and let his hands go in a furiously paced round four. Mailata appeared to punch himself out and was forced to defend against right hooks and straight left hands from the towering southpaw who clearly caught his second wind and a world of confidence in a pivotal round.

Mailata once again hurt Mireles in round five but could not replicate what he was able to accomplish earlier in the fight. Mireles was the busier fighter until he was clipped upstairs by Mailata, who followed up with wide hooks and right hands that mostly missed the mark. Mireles rallied to land a right hook later in the frame.

Mireles punched in combination to open the sixth and final round. Mailata walked through the incoming but was too fatigued to sufficiently follow up and was forced to instead tie up at close quarters. Mireles remained the busier fighter and was able to maintain his desired pace during the moments when the 321-pound Mailata didn’t clinch and lean on Mireles’ chest. The crowd booed the lack of action in the closing seconds.

Mireles advanced to 7-0 (6KOs) as he earned his first decision win. Mailata suffered his second defeat in his past four fights as his record fell to 6-2 (3KOs).

Headlining the show, former titlists Jose Ramirez (27-1, 17KOs) and Richard Commey (30-4-1, 27KOs) will collide in a scheduled 12-round junior welterweight bout. The card also features a strawweight title unification fight between WBA champ Seniesa Estrada (23-0, 9KOs) and long-reigning WBC queen Tina Rupprecht (12-0-1, 3KOs).

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