Carlos Cuadras didn’t have the luxury of enjoying his first full day in Phoenix ahead of his upcoming fight this weekend.

Instead, he had to cram for his next opponent, unbeaten late replacement Jesse Rodriguez. The opponent switch came overnight, with San Antonio’s Rodriguez (14-0, 10KOs) replacing Thailand’s Srisaket Sor Rungvisai who has been in town since last Wednesday but who fell ill over the weekend. Event handlers were swift in securing a new foe for Mexico City’s Cuadras, who was suddenly left with homework to begin fight week.

“It surprised me,” Cuadras told BoxingScene.com. “I admit I really don’t know a lot about Jesse Rodriguez. I just started watching videos on him (Monday) morning. I know that he trains hard and that he’s Joshua Franco’s brother – I didn’t even know they were brothers until (Monday).”

Rodriguez campaigns at junior flyweight where he plans to return regardless of the outcome of Saturday’s DAZN main event at Footprint Center in Phoenix. A win by Rodriguez will leave the brothers as junior bantamweight titleholders, with the vacant WBC belt at stake. Franco holds a secondary version of the WBA 115-pound title and is presently due a mandatory shot at lineal/WBA “Super” champion Juan Francisco Estrada (42-3, 28KOs).

A win by Cuadras (39-4-1, 27KOs)—a former WBC champ—this weekend could create an entirely new rivalry, perhaps prompting Franco to avenge his brother’s loss if it should come to that.

"I hope (Franco) calls me out after I win,” Cuadras admits. “This way I can beat up the whole family."

For now, the 33-year-old Cuadras has to mentally prepare for a stud talent more than ten years his junior. The 22-year-old Rodriguez—who trains out of the Robert Garcia Boxing Academy in Riverside, California—is viewed as a can’t-miss rising contender, his confidence evident in his willingness to move up in weight and to fight on the title stage literally at a moment’s notice.

“He trains with Robert Garcia, which tells me he will come in very well prepared,” acknowledges Cuadras. “But if I’m being honest, I really didn’t know much about him before then.

“I know I have to change my approach. I have my style and that is what I will apply. I also have to adjust to a faster opponent. Sor Rungvisai is a little bit of a slow fighter. From what I can see, this young man is very quick.”

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox