Seniesa Estrada defended her WBA 105-pound title in spectacular fashion Saturday night.

Estrada emphatically dropped previously unbeaten Maria Micheo Santizo once apiece in the third and fourth rounds before their scheduled 10-round championship match was stopped at AT&T Center in San Antonio. Referee Mark Calo Oy immediately stopped the action at 1:31 of the fourth round, once Estrada’s straight left sent Santizo crashing to the canvas again on DAZN’s Gilberto Ramirez-Yunieski Gonzalez undercard.

The 29-year-old Estrada, of East Los Angeles, California, improved to 22-0 and recorded her ninth knockout. Guatemala’s Santizo, 36, lost for the first time in three years as a pro (9-1, 5 KOs).

Santizo knocked Estrada off balance with a right hand 20 seconds into the third round. Santizo, perhaps overconfident after landing that punch, got clipped several seconds later with a counter left hook by Estrada that sent Santizo crashing to the canvas.

Santizo got up by the time Calo oy counted to six. Her legs weren’t steady when the action resumed, which enabled Estrada to rock her with a right hand toward the end of the third round.

Santizo survived that onslaught, though, and remained on her feet until the bell sounded.

Estrada tried to overwhelm Santizo with volume punching in the opening minute of the second round. That didn’t stop Santizo from winging wild shots that occasionally landed in what amounted to an entertaining two minutes.

Estrada countered Santizo with a left hook about a minute into the opening round. Estrada slipped most of Santizo’s punches until Santizo landed two flush right hands in the final 20 seconds of that first round.

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