Unbeaten Seniesa "Super Bad" Estrada (21-0, 8 KOs) will be putting her WBA minimumweight world title on the line against Maria "La Imparable" Santizo (9-0, 5 KOs) in a 10-round DAZN co-main event on December 18.

Estrada drops back in weight after capturing the WBO junior flyweight title in her last contest.

The event is headlined by light heavyweight contender Gilberto "Zurdo" Ramirez (42-0, 28 KOs), who takes part in a WBA light heavyweight eliminator against the dangerous Yunieski "The Monster" Gonzalez (21-3, 17 KOs) at San Antonio's AT&T Center.

Estrada is taking no chances in the fight with Santizo and expects a tough battle.

"Texas is a great fight state. I fought in Texas as an amateur, and I recently fought in Texas this past March for the world title and the atmosphere was amazing. To be coming back and defending my world title in San Antonio, I know the fans are going to be great so I am very excited to be coming back. I love Texas," Estrada said.

"I go into every fight thinking that every opponent is a threat so I never overlook any opponent. She's 9-0, so it's a good match up, two undefeated fighters. I have been studying her a lot and have learned her strengths and I see her weakness. I just have been preparing myself to be the best that I can be, fixing any mistakes that I make, and overall just making myself better in every-way.

"Now being a two-division world champion, I thinking that I have to continue to be even more focused and not get too comfortable. I feel like my mentality is so much stronger going into this fight because I know that I am a multiple world champion and I want to keep it that way. It's like what Oscar said to me 'winning a world championship is one thing, but to keep it and remain champion is more difficult.' And that is something that has stuck with me, because he is so right about that."