A can’t-miss action fight between unbeaten Mexican knockout artists lived up to the billing, even in going the distance.

Lindolfo Delgado fended off a determined Omar Aguilar to escape with his unblemished record intact following an eight-round, unanimous decision win. Judges Jerry Cantu (77-75), Pat Russell (79-73) and David Solivan (79-73) all scored in favor of Monterrey’s Delgado in their terrific junior welterweight battle Saturday evening at Pechanga Arena in San Diego.

In what was billed as the potential fight of the night, the matchup of undefeated punchers brought the pain early in the fight. Delgado was calm out the gate, allowing Aguilar to come forward and countered with left hooks. Aguilar was the busier fighter, though also paying the price for attempting to initiate a firefight as his nose was bloodied while also showing swelling atop his right cheek.

Aguilar wasn’t scared off by the sight and feel of his own blood, continuing to take the fight to Delgado. Aguilar was losing the battle of the jabs but was able to push through those sequences to come back with left hooks and looping right hands around Delgado’s guard. Delgado was the more efficient puncher, though being outworked by the taller Aguilar after controlling the pace in the opening round.

Delgado used more movement in round three, though Aguilar quickly cut off the ring and let his hands go on the inside. Delgado shook off a left hook from Aguilar to respond with a left uppercut and right hand at center ring. Aguilar attempted to respond with a chopping right hand, though beaten to the punch with a straight right from Delgado.

Aguilar walked directly into a right uppercut that had him badly in trouble early in round four. Delgado attempted to follow up, only for his countryman to clinch before falling to the canvas. The sequence was ruled a slip but didn’t deter Delgado from continuing with his measured onslaught. Aguilar managed to remain upright the rest of the round as Delgado let his hands go to the tune of landing a blistering 59 percent of his power punches (24-of-41) in the round.

Prior swelling transitioned to a full-blown mouse under Aguilar’s right eye as Delgado boxed with confidence in round five. Constant movement by the 2016 Olympian proved troubling for Aguilar, who continued to follow his countryman around the ring while absorbing jabs. Aguilar responded with a volley of punches in the final minute, though Delgado managed to avoid most of the incoming.

Aguilar bounced back in round six, persistently coming forward and finally reaping the dividends as a right hand briefly stunned Delgado. The singular moment quickly passed, as Delgado was able to connect upstairs before moving out of harm’s way. Aguilar landed a right hand down the stretch, following up with a flurry before getting caught with two straight right hands in the final ten seconds of the round.

Delgado was once again encouraged by trainer Robert Garcia Jr. to keep his back off the ropes. A brief lapse by the unbeaten Mexican was exploited by Aguilar, who landed with an overhand right while fighting through a rapidly swollen shut right eye in his best effort to close the gap on the scorecards. Delgado returned to boxing, though his power shots not carrying the same heat as Aguilar never stopped coming forward.

The eighth and final round saw Delgado fend off fatigue and an onrushing Aguilar, who was constantly on the hunt. Delgado continued to move, catching Aguilar with counter right hands. Aguilar walked inside, hoping to land a tide-turning shot but disallowed that opportunity by the superior boxer in Delgado who managed to outland his countryman 149-to-138 overall.

Delgado—who landed 94-of-188 (50%) power punches—improves to 16-0 (13KOs) with his best win to date. Aguilar (24-1, 23KOs) fell short in his first career fight past six rounds, having not been extended beyond the third round during his 12-fight knockout streak that came to an end.

Delgado-Aguilar aired live atop the ESPN+ preliminary undercard preceding an ESPN tripleheader. Headlining the show, WBO featherweight titlist Emanuel Navarrete (35-1, 29KOs) attempts his third title defense as he faces first-time title challenger Eduardo Baez (21-2-2, 7KOs).

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