Mayweather, who retired with a perfect 50-0 record, made the admission about a training session from 2013. He was preparing for his fight with Robert Guerrero when a young Spence Jr. gave him a run for his money.
In a recent interview with FightHype TV, Mayweather said:
"Errol Spence, he's a hell of a fighter. One thing about me, I'm always going to give it to you 100% you know, and in training camp, when I was training for my fight with [Robert] Guerrero, Errol Spence gave me solid work."
Mayweather's career was filled with impressive victories over top-tier opponents. He beat the likes of Manny Pacquiao, Canelo Alvarez, Ricky Hatton, Miguel Cotto, and Oscar De La Hoya. The fact that he singles out Spence Jr. speaks volumes about the young fighter's skills.
"He's a very young, tough competitor, so if I sit here and not give that young kid props, it'll be bad. Even though after doing my time I'd been off a year, he took me to the limit, he made me work in the boxing gym, I like kids like that."
Spence Jr. has lived up to that early potential. He raced to a 22-0 record early in his career and won his first world title by knocking out Kell Brook in Sheffield. He went on to defend his title against Lamont Peterson and Mikey Garcia before adding the WBC strap in a tough fight with Shawn Porter.
More big wins followed against Danny Garcia and Yordenis Ugás, making Spence Jr. a three-belt champion. His most recent fight was a historic undisputed contest against Terence Crawford in July 2023.
Crawford stopped Spence Jr. in the 9th round to become the undisputed welterweight champion. Spence Jr. hasn't fought since, but reports suggest he will soon move up to 154 lbs.
As for Crawford, he's already made that move. He became a world champion at 154 lbs, making him an undisputed champion in two weight classes.
Mayweather's praise for Spence Jr. shows the respect top fighters have for each other. It also highlights how a tough sparring session can stick in a fighter's memory, even years later.