Bob Santos is now working with former junior middleweight boss Jeison Rosario, who has moved up to the middleweight division. The trainer hopes that Rosario’s career will resemble that of football great Jim Plunkett.

Rosario, still only 29, last fought in November, securing a second-round stoppage over Israel Valerio Nina in the Dominican Republic. This victory followed his brutal 2022 loss to Brian Mendoza, where he was knocked out in five rounds.

Rosario (24-4-1, 18 KOs) held the WBA and IBF junior middleweight titles when he defeated Julian “J-Rock” Williams, stopping the Philadelphia fighter in his hometown. Santos sees a parallel to former NFL great Plunkett, whose career was defined by a remarkable comeback. Plunkett, initially viewed as a draft bust, became a two-time Super Bowl winner as a starting quarterback with the Oakland Raiders. Rosario has already held a title and, thus, many observers feel his best days are behind him.

"I'll give you a little bit of analogy or a backstory with another sport, and I'm sure you know who this is, Jim Plunkett – so that's what I'm doing with him, a little bit, you know what I mean, bringing him back a little bit slowly but surely, kind of like Al Davis did with Jim Plunkett," Santos said. "Everybody wrote him off and said he was completely done. There was nothing left from a football analogy, and he went on to win two Super Bowls."

For those unfamiliar with general sports, Santos offered a boxing comparison: "James Toney, everybody wrote him off," Santos said. "I remember when James first made his comeback. Everybody said he was done. He was 300-something pounds. Started getting back in shape when he first got back in the gym, and we all seen what he ended up doing. He won the cruiserweight championship of the world, and the heavyweight championship of the world [though he was later stripped after failing a drug test], and he was definitely written off by everybody when he made the comeback. No two ways about it."

Regardless, a comeback of similar proportions for Rosario is still a stretch. His three losses include brutal knockouts to Jermell Charlo and Erickson Lubin in back-to-back fights and then, two years ago, he was stopped by Mendoza. Santos remains very optimistic about what he sees so far in the gym.

"Hopefully he gets a fight sooner rather than later," Santos said. "We're trying to turn the tide around for him. We'll see how much left he has in the tank. He’s grinding away and plugging away. We'll see how that works out."

When asked about a timeline for Rosario's return, Santos was concise and optimistic, suggesting a date in August, though no exact date has been set.