Robert Rodriguez demolished Abel Soriano on Saturday night.

The unbeaten southpaw knocked down the previously undefeated Soriano three times in the first round. Referee Russell Mora stopped their scheduled six-round junior featherweight fight with just one second to go in the opening round.

ESPN+ streamed Rodriguez’s impressive victory from MGM Grand Conference Center in Las Vegas as part of the Eleider Alvarez-Joe Smith Jr. undercard.

The 21-year-old Rodriguez (9-0-1, 5 KOs), of Riverside, California, first floored Soriano (10-1, 7 KOs) with a well-placed left to the body. Soriano, in excruciating pain, fell to his gloves and knees with 1:17 to go in the first round and barely beat Mora’s count.

Soriano, of Bellevue, Nebraska, then took a knee with 42 seconds to go in the first round after taking a right to the body. Rodriguez swarmed him again once Mora brought them together and ended the fight with a stiff jab that left Soriano flat on his back.

In the bout before Rodriguez’s win, Israel Mercado went the distance for the first time as a pro, but he convincingly beat a previously undefeated opponent.

Mercado connected with the harder punches for most of his six-round junior welterweight fight against Adrian Valdovinos and was rewarded accordingly by the three judges. Lisa Giampa (60-54) and Glenn Trowbridge (60-54) scored all six rounds for Mercado, who won five of the six rounds on Dave Moretti’s card (59-55).

The Pomona, California, native’s unanimous-decision win moved Mercado’s record to 8-0 (7 KOs). Valdovinos, of Hanford, California, slipped to 5-1-1 (4 KOs).

Mercado connected with the harder punches for most of his six-round junior welterweight fight against Adrian Valdovinos and was rewarded accordingly by the three judges. Lisa Giampa (60-54) and Glenn Trowbridge (60-54) scored all six rounds for Mercado, who won five of the six rounds on Dave Moretti’s card (59-55).

The Pomona, California, native’s unanimous-decision win moved Mercado’s record to 8-0 (7 KOs) on the Eleider Alvarez-Joe Smith Jr. undercard, which ESPN+ streamed from MGM Grand Conference Center in Las Vegas. Valdovinos, of Hanford, California, slipped to 5-1-1 (4 KOs).

Referee Jay Nady called for a brief break in the action early in the sixth round because Valdovinos was hurt by an accidental clash of heads. Valdovinos continued to move forward throughout the final round, but Mercado was more active and accurate with his shots.

Mercado got back to boxing during what evolved into a one-sided fifth round. He landed a three-punch combination just after the midway mark of the fifth, which left Valdovinos bleeding from his nose.

Mercado drilled Valdovinos with a right hand late in the fourth round, but Valdovinos landed the harder punches for most of those three minutes.

Valdovinos kept pressuring Mercado in what was a more successful third round for him. He landed several right hands in that round.

Mercado continued connecting with right hands and later left hooks in a second round he clearly won.

Mercado got off to a very strong start. He almost couldn’t miss Valdovinos with his right hand in the first round, when he fought effectively off his back foot.

In the first fight Saturday night, Wendy Toussaint easily defeated Isiah Jones to remain unbeaten.

The junior middleweight prospect consistently landed his right hand, kept pressure on Jones throughout their eight-round bout and won by unanimous decision. The 28-year-old Toussaint won by scores of 80-72, 79-73 and 79-73.

The Haitian-born Toussaint, of Huntington, New York, improved to 12-0 (5 KOs). Detroit’s Jones (9-3, 3 KOs), who fought for the third time since June 16, has lost three of his past four fights.

Toussaint drilled Jones with a right hand just before the halfway mark of the eighth round. Jones mostly kept away from him for the remainder of that round to reach the final bell.

Jones made Toussaint miss with several right hands in the seventh round, but he didn’t land many punches of his own.

Toussaint stung Jones with three straight rights and a right uppercut within the first 45 seconds of the sixth round. Jones appeared to be hurt, but Toussaint couldn’t capitalize.

A right hand by Toussaint knocked out Jones’ mouthpiece just before the halfway point of the fifth round. Another overhand right by Toussaint backed Jones into the ropes toward the end of the fifth.

Toussaint snapped back Jones’ head with a stiff jab midway through the fourth round. Several seconds later, Toussaint nailed Jones with an overhand right that knocked Jones into the ropes.

A right hand by Toussaint caught Jones as he moved backward 50 seconds into the third round. Toussaint pressed the action and threw his jab for much of the second round. The best punch of that round was a chopping right hand by Toussaint.

Toussaint landed a right to Jones’ body that moved him into the ropes 45 seconds into the opening round.

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