MINNEAPOLIS – The last time an American audience watched Jeison Rosario box, Erickson Lubin dropped the former champion twice and stopped him in the sixth round of their 154-pound elimination match.

Sixteen months later, a refreshed Rosario will battle Brian Mendoza in a 10-round middleweight bout Showtime will televise Saturday night from The Armory. For Rosario, it’s an opportunity to prove he still has championship-caliber boxing in his 27-year-old body after back-to-back knockout defeats to undisputed 154-pound champion Jermell Charlo and Lubin.

Rosario regained some of his confidence by stopping three nondescript opponents over the past 11 months in Santo Domingo. More than anything, though, Rosario (23-3-1, 17 KOs) has benefitted from boxing above the junior middleweight limit.

Squeezing down to 154 pounds became such a tortuous process for the 6-foot Rosario that the former IBF/IBO/WBA champion couldn’t endure the physical and mental anguish anymore.

“It was so hard,” Rosario told BoxingScene.com through a translator Thursday prior to a press conference at W Minneapolis The Forshay. “My health was being compromised.”

The contract weight for Rosario’s fight against Mendoza is 160 pounds, the middleweight maximum.

“It’s like night and day,” Rosario said. “I feel more comfortable, stronger. It’s been less of a sacrifice to make. I love it.”

Albuquerque’s Mendoza (20-2, 14 KOs) replaced Rosario’s original opponent, Cuban southpaw Yoelvis Gomez, on barely 10 days’ notice. The 25-year-old Gomez (6-0, 5 KOs) wanted to take a significant step up in class versus Rosario in what would’ve been an intriguing bout, but Rosario still can’t wait to prove that he remains a formidable fighter.

“You’re gonna see a different fighter in every sense of the word,” Rosario said. “Faster, stronger, more active, because when I was at 154, I had to get my body to the breaking point. When you do that, and when you ask your body to break itself down so much, you’re not gonna be anywhere near a hundred percent. Now you’re gonna see me really be able to display everything I can display.”

Rosario, who walks around at approximately 195 pounds, wants to become the first fighter to stop Mendoza inside the distance. The 28-year-old Mendoza has lost only on points to undefeated junior middleweight contender Jesus Ramos (19-0, 15 KOs), a 10-round unanimous decision, and Larry Gomez (10-2, 8 KOs), an eight-round split decision.

“You’ll see a different ‘Banana,’” Raul “Chino” Rivas, Rosario’s new trainer, told BoxingScene.com in reference to his fighter’s nickname. “He’s happy. Camp was amazing. He got beautiful work. We had a transition in the last week-and-a-half to Mendoza. It’s a big difference, from a southpaw to a right-handed fighter. But he has the same mentality because Mendoza has never been stopped. He wants to make a statement.

“When that bell rings, we’ll press, press, press. The goal is to get him out of there. We don’t want to do 10 rounds. But I also informed him that if he goes 10 rounds, don’t worry about it. The goal is to get the ‘W.’ He can look sharp doing 10 rounds. Either way, people will acknowledge the difference from where he was to where he is now.”

Rosario-Mendoza will be broadcast just before Showtime’s main event – a 12-round, 168-pound championship match in which Cuban southpaw David Morell Jr. (7-0, 6 KOs) will make a mandated defend of his secondary WBA belt against Kazakhstan’s Aidos Yerbossynuly (16-0, 11 KOs). Showtime’s telecast is scheduled to start at 9 p.m. ET, with a 10-round middleweight bout between Polish middleweight prospect Fiodor Czerkaszyn (20-0, 13 KOs) and veteran Nathaniel Gallimore (22-5-1, 17 KOs), of Des Plaines, Illinois.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.