Jussie Smollett 'Attacker' Abel Working with Floyd Mayweather Jr.'s Trainer

Unlike Jussie Smollett, at least one of his alleged "attackers" is seeing his career on the upswing ... Abel Osundairo is now training with one of Floyd Mayweather Jr.'s trainers.

We're told Abel met Nate "The Snake" Jones through a well-connected boxing family in Chicago and they recently met up at Taylor Park Gym in Chi-Town to get in the ring and train. Nate's name carries weight in the boxing world ... the former pro heavyweight joined Mayweather Promotions as a trainer a little over a year after retiring and has trained Floyd in about a dozen fights ... including vs. Manny Pacquiao.

As we've reported ... Abel showed promise after mowing down opponents at the Golden Gloves tournament ... scoring first-round TKOs, unanimous decisions and, most recently, a first-round TKO in the senior novice 178-pound division to win the prestigious tourney.

Abel's still a raw talent -- he competed in a division for less experienced boxers between 21 and 35 who weigh 178 pounds or less -- but there's potential ... and further proof that if the Osundairo brothers really wanted to hurt Jussie in the "attack" ... it would've been vicious.

As you know ... Abel's lawyer says Jussie told them he wanted Abel to "attack" him, but not rough him up too badly. Since the "attack" ... Abel and his bro have struggled to land acting gigs but Abel's fortunes might have turned with Nate -- a former U.S. Olympic Boxing medalist -- now in his corner.

We're told Abel's training sesh wasn't a one-off, 'cause they plan to continue training. It's unclear if Nate thinks Abel's got what it takes to turn pro ... but training with a decorated trainer like Nate is a strong sign Abel's serious about boxing.