LAS VEGAS – Andres Cortes violently knocked out Alexis del Bosque on Saturday night.

A devastating right-left-right combination by Cortes knocked del Bosque to the canvas 34 seconds into the sixth round on the Shakur Stevenson-Oscar Valdez undercard at MGM Grand Garden Arena. A disoriented del Bosque attempted to get up and fell again.

He reached his feet on his second attempt, but referee Celestino Ruiz quickly determined del Bosque was unfit to continue. Ruiz officially stopped a lightweight fight scheduled for eight rounds 43 seconds into the sixth round.

Las Vegas’ Cortes upped his record to 17-0 and produced his 10th knockout. Dallas’ del Bosque dropped to 18-6-1 (9 KOs) and suffered just his second knockout defeat in his nine-year, 25-fight pro career.

Before he finished del Bosque during the sixth round, Cortes bloodied the area around del Bosque’s left eye, bombarded him with power punches and made him take a knee with 1:25 to go in the fourth round.

A determined del Bosque reached his feet, survived Cortes’ ensuing onslaught and made it to the fifth round. Cortes hammered him with power punches throughout the fifth round, though, before stopping him in the early in the sixth.

In the previous fight Saturday, Troy Isley’s commitment to body punching paid off.

The developing prospect dropped Anthony Hannah twice during the second round and won their scheduled six-round middleweight match by technical knockout. Referee Robert Hoyle halted the action after Hannah went to the seat of his trunks from a right hand to his body, officially 2:33 into the second round

Isley, of Alexandria, Virginia, improved to 5-0 and recorded his third knockout. Hannah, of Augusta, Georgia, fell to 3-3 (2 KOs) and lost inside the distance for the second time as a pro.

About 40 seconds before that second knockdown, Isley’s left to the body sent Hannah down for the first time. A right hand that snuck around Hannah’s guard did the damage to Hannah’s head before Isley’s left to the body put him down.

In the bout before Isley’s victory, Abdullah Mason displayed again why his handlers are so excited about the 18-year-old lightweight prospect’s future.

The skillful, strong southpaw overwhelmed Luciano Ramos with his hand speed and power for 2½ minutes, until referee Tony Weeks stepped between them to stop their scheduled four-rounder.

Mason’s left to the body and a follow-up left to Ramos’ head made the Argentine fighter move away. Sensing the end was near, Cleveland’s Mason (2-0, 2 KOs) followed Ramos (1-3, 0 KOs) across the ring and unloaded more punches, enough to make Weeks intervene.

The official time of the stoppage was 2:32 of the first round. Ramos was upset by the stoppage and shoved Mason several seconds after their brief bout ended.

It seemed Mason’s second pro fight wouldn’t last long when his right-left combination backed up Ramos less than 20 seconds into the fight. Mason later landed a hard left hand that knocked Ramos off balance with just over a minute to go in the first round.

Before Abdullah’s dominant win, a dismayed Jaylan Phillips walked away from referee Kenny Bayless and slammed something to the canvas once the official result was read by ring announcer Mark Schunock.

Phillips, and seemingly most of the sparse crowd in attendance for the first fight on the Stevenson-Valdez undercard, thought he had done more than enough to upset junior welterweight prospect Antoine Cobb. Only one judge, Ricardo Oscasio, scored their four-round fight for Phillips, 39-37.

The other two judges, Tim Cheatham and Lisa Giampa, scored the action even, 38-38, which left Atlanta’s Phillips to settle for a majority draw.

Phillips (1-2-1, 1 KO) still performed well in his second fight since Mason stopped him in the second round November 5 at nearby Virgin Hotels Las Vegas. Chicago’s Cobb slipped to 1-0-1 (1 KO).

An aggressive, accurate Phillips appeared to be in control when he connected with a hard right to the body just before the halfway point of the fourth round and final round. A three-punch combination by Phillips made Cobb retreat with just under a minute to go in the last round.

A straight left by Phillips got Cobb’s attention about 35 seconds into the third round. With Cobb bleeding from a cut beneath his left eye, Phillips landed a right hook that made Cobb move away from him with about 50 seconds to go in the third round.

Cobb appeared tired as he walked toward his corner after the third round.

Phillips caught Cobb with a left hook just before the midway mark of the second round. Just before the second round concluded, a straight right hand by Cobbs moved Phillips backward.

Cobb connected with the flusher punches during the first round, but Phillips seemed to gain control in the second round.

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