The Mexican faced Frampton in a 2015 bout
Mexican boxer Alejandro González Jr. was found dead near his home in Mexico in the early hours of Friday morning.
González Jr., whose father Alejandro Martín González held the WBC featherweight and IBC lightweight titles during his career, had a record of 25 wins in his 31 fights, including 15 knockouts. His most recent fight took place at the end of October against Hector Bobadilla, which was ruled a majority decision draw.
Carl Frampton faced González Jr. in Texas in July of 2015, and took to Twitter in the wake of learning the news to pay tribute to his former opponent.
Describing him as "one of the nicest guys I've shared a ring with," Frampton added that their bout in Texas had been a hugely difficult fight, in which he was knocked down a number of times.
"This kid gave me the fright of my life. But kept in touch from time to time on WhatsApp and always wished me well," Frampton added. "Very sad, RIP Champ".
Image: ©INPHO/Presseye/Ivan Pierre Aguirre
Frampton's wife Christine also paid tribute to the late fighter, saying that the two had spoken about family when the fight took place in Texas last year.
Absolutely heartbreaking news about the passing of Alejandro Gonzalez jr. Spoke at length with him in El Paso about our families. So sad— Christine Frampton (@XtineDorrian) December 9, 2016
Premier Boxing Champions (PBC) issued a statement on their website about the fighter, describing the death of the young star, whose nickname was 'Cobrita', as a tragic loss.
"Everyone at Premier Boxing Champions is profoundly saddened by the death of Alejandro Gonzalez Jr. He was a fantastic boxer with a bright future," said Tim Smith, Vice President of Communications for PBC. "It is a tragic loss for the boxing community. We offer our deepest condolences to his family and pray for them as they cope with the loss of their beloved 'Cobrita'."
Mexican newspaper El Universal report that the fighter's death is being investigated as a murder, but that there is not yet any known motive.