In October 2018 Pacheco signed with
Eddie Hearn's
Matchroom Boxing USA. He made his professional debut on December 22, 2018, at the
Auditorio Fausto Gutiérrez Moreno in
Tijuana, Mexico, against Luis Carlos Gonzalez, winning by
knockout (KO) early in the first round. In 2019, he fought and won seven times, including six victories by way of KO. On December 7, 2019, he featured on the undercard of
Andy Ruiz Jr. vs Anthony Joshua II in
Riyadh, Saudi Arabia, knocking out the more experienced opponent Selemani Saidi with a right hand. On February 29, 2020, Pacheco defeated Oscar Riojas via six-round
unanimous decision (UD) on the undercard of
Mikey Garcia vs.
Jessie Vargas at the
Ford Center at The Star in
Frisco, Texas. On March 5, 2022 Pacheco stopped Genc Pllana in the second round. On June 10, 2022 he defeated Raul Ortega via fourth-round RTD. On April 6, 2024 in Las Vegas, Pacheco was scheduled to face Shawn McCalman. He won the fight by unanimous decision and retained his WBC USA and WBO International super middleweight titles. Pacheco was scheduled to face former title challenger
Maciej Sulecki in Carson, CA on August 31, 2024. Pacheco won the fight by knockout in the sixth round with liver shot. Pacheco beat Steven Nelson by unanimous decision in Las Vegas on January 25, 2025. He recovered from being knocked to the canvas in the eighth round to defeat the previously unbeaten
Kévin Sadjo via unanimous decision to claim the
WBC Silver super-middleweight title at
Stockton Arena in
Stockton, California, on December 13, 2025. == Fighting style ==