Floyd Mayweather ended his career with a stoppage win over UFC champion Conor McGregor, but it was the fight before that caused drama.
Floyd Mayweather ended his career with a highly viewed crossover bout in which Conor McGregor made his boxing debut. The build-up for the fight was nothing short of dramatic and the fight delivered with Mayweather securing a tenth-round knockout of the Irishman.
In his previous fight, Mayweather won a wide unanimous decision against Andre Berto, though it was this fight that caused much drama beforehand.

Floyd Mayweather’s fight with Andre Berto was personal after amateur rivalry
In 2015, two years before Mayweather, who sparred Errol Spence in an exhausting war, returned to boxing for the McGregor fight, he made a defense of his WBC welterweight title against 30-3 Andre Berto.
The fight was criticized as Berto was 3-3 in his last six fights, and many believed he was no longer of the caliber to provide a good fight for Mayweather, whose uncle was stopped by Oscar De La Hoya, especially since there were multiple other contenders for the fight.
Kell Brook was reportedly considered but not chosen due to his lack of notoriety in the US, and Amir Khan spoke to Sky Sports about not being picked despite being one of the frontrunners:
“I’m disappointed not to have got the fight for what is the third time after having been one of the front-runners.”
Khan, who was dismantled by Canelo, never got the Mayweather fight, and Berto believes he was chosen not for his resume, but for personal reasons.
According to Bad Left Hook, Berto said: “I don’t know what’s going through his head,” Berto shrugged off. “We know a lot of the same people so it must be something. [The media doesn’t] think I deserve this fight so he must be trying to beat me up for a reason. Every other fighter makes sense but before he leaves he wants to fight me.”
Berto stated he believed his win in the National Golden Gloves tournament rattled Mayweather, despite him taking Berto out for dinner to congratulate him, and may be one of the reasons Mayweather wanted to fight him before hanging up the gloves.
Floyd Mayweather announced his retirement after the Andre Berto fight and was pleased to beat one special record
After his fight, BoxRec reports that Mayweather said: “My career is over. It’s official.”
He spent 17 years of his 19-year career as a world champion, but knew to hang up the gloves before it was too late:
“You got to know when to hang it up, and it’s time for me to hang it up […] I’m not going to be doing this when I’m 40 years old.”

Mayweather, who scored a KO in his debut, was told that he’d matched Rocky Marciano’s record, which was the greatest in boxing history for a fighter who was champion when they retired, to which Mayweather said:
“That means it’s part of boxing history. Records are made to be broken. Hopefully, we can find the next Floyd Mayweather who can break the record.”