Undefeated MMA Phenom Answers Call to Debut at UFC Mexico after Fight Week Withdrawal

One of Mexico’s brightest young MMA talents is stepping up to make their UFC debut on short notice this weekend in Mexico City.

The UFC returns to the Arena CDMX in Mexico City this Saturday night with a card that was supposed to see two-time UFC Flyweight Champion Brandon Moreno take on Asu Almabayev before Almabayev unfortunately withdrew from the event with an injury.

Lone’er Kavanagh is now set to take on Moreno in the night’s main event. Marcel Dorff reports that the card has also undergone another major change during fight week, as Regina Tarin will step in to make her promotional debut in a 130-pound catchweight bout against Ernesta Kareckaite after Sofia Montenegro pulled out of their scheduled women’s flyweight contest.

Regina Tarin Answers Call To Debut At UFC Mexico

A perfect 7-0 since turning pro in 2023, Tarin has secured finishes in all of her pro outings other than a 2024 meeting with Andrea Garcia that she won via unanimous decision.

Three out of her first four fights ended inside the opening round, and in 2024 the 21-year-old claimed the vacant Budo Sento Championship women’s bantamweight belt with a fourth-round TKO against Luisa Cifuentes. Tarin returned to Combate Global in the summer of last year and also stopped Kaytlin Neil, who competed on Season 30 of The Ultimate Fighter.

“Kill Bill” last competed in November at Tough N Xtreme 1125 in Costa Rica, where she knocked out Yuriva Jimenez just over two minutes into their co-main event fight.

Ernesta Kareckaite Aims To Spoil UFC Debut For "Kill Bill"

Tarin was scheduled to compete in a Muay Thai bout at Budo Sento Championship 33 this week before stepping up to face Kareckaite, who earned a UFC contract on Dana White’s Contender Series in 2023.

After extending her unbeaten record with a split decision win over Carli Judice on DWCS, Kareckaite was matched up with Dione Barbosa for her promotional debut at UFC 301 and lost a unanimous decision. “Heavy-Handed” returned in January of 2025 to take a split decision over Nicolle Caliari, and the Lithuanian will return from more than a year on the sidelines when she welcomes Tarin to the UFC this weekend.

Dione Barbosa (red gloves) fights Ernesta Kareckaite (blue gloves) during UFC 301 at Rio Arena. | Jason Silva-Imagn Images

Tarin was almost certainly already on the UFC’s radar for a potential DWCS opportunity of her own before being called to fight at UFC Mexico City, and she joins a number of other Mexican fighters that will be looking to score big wins in their home country.

UFC Mexico Fight Card

• Main Event: Brandon Moreno vs. Lone’er Kavanagh

• Co-Main Event: Marlon Vera vs. David Martinez

• Daniel Zellhuber vs. King Green

• Edgar Chairez vs. Felipe Bunes

• Imanol Rodriguez vs. Kevin Borjas

• Santiago Luna vs. Angel Pacheco

• Jose Medina vs. Ryan Gandra

• Macy Chiasson vs. Ailin Perez

• Christian Quiñonez vs. Kris Moutinho

• Douglas Silva de Andrade vs. Javier Reyes

• Ernesta Kareckaite vs. Regina Tarin

• Erik Silva vs. Francs Marshall

• Wes Schultz vs. Damian Pinas