As he prepares for that big fight - one that will draw in viewers who've never watched a boxing match in their lives - much of the coverage of Mayweather's life outside the ring has focused on his wild spending habits.
We all know he buys more luxury cars than he can possibly drive, spends $1,000 per meal, and flaunts his extreme wealth more than any other athlete alive.
But before the biggest fight of his career another, darker aspect of his life outside the ring is resurfacing.
Mayweather has a long history of domestic violence.
Since 2002 Mayweather has been accused of violence against women with alarming frequency. He pleaded guilty in two of those incidents, and in another he was convicted only to have the charges dismissed four years later. The most recent incident, in which he hit his ex-girlfriend in front of two of their children at 5 a.m. in 2010, resulted in a 90-day prison sentence.
Those three incidents:
1. Over a five-month span in 2001 and 2002 he pleaded guilty to two counts of battery domestic violence, a search of his criminal record on the Clark County website shows. He received 48 hours of community service and two days of house arrest. Three other charges - stalking, obstruction of a police officer, and violation of a protective order - were dismissed.
According to the Las Vegas Review-Journal, Melissa Brim, the mother of Mayweather's oldest daughter, was the victim. She later claimed in a lawsuit that Mayweather "swung open a car door, hitting her jaw, pushed her into the car and punched her several times in the face and body," the Review-Journal reports.
That lawsuit was dismissed in 2003, according to the Review-Journal.
In the press conference for his 2002 fight against Jose Luis Castillo, Mayweather was asked about the conviction and said, "Everybody that knows Floyd Mayweather, knows I'm a good guy. I have never been to jail."
2. In November 2003 Mayweather was arrested and charged with two counts of battery for allegedly fighting with two women at a Las Vegas nightclub. He was later convicted of misdemeanor battery and ordered to serve 100 hours of community service, the Associated Press reported at the time. According to the AP, one of the accusers, Herneatha McGill, testified that Mayweather "punched [her] on the cheek, and then punched [Kaara] Blackburn on the back of the head as she tried to help her friend."
A search of Mayweather's criminal record shows these charges were "dismissed per negotiation" in 2008.
3. In December 2011, Mayweather pleaded guilty to one count of misdemeanor battery domestic violence and no contest to two counts of harassment for hitting the mother of three of his children. He was sentenced to 90 days in jail and released after 60 days.
According to the arrest report, the victim, Josie Harris, got home at 2:30 a.m. on a night in September 2010 to find Mayweather talking to their two sons. The two got into a verbal altercation and Harris called the police, the report said.
The police report said Mayweather left after the police arrived, but returned at 5 a.m. with his friend James McNair.
Harris told police that she woke up to Mayweather standing over her reading her text messages. When she admitted she was dating someone, he allegedly started hitting her.
Harris told police that Mayweather hit her in the back of the head, pulled her off a couch by her hair, and told her, "I'm going to kill you and the man you're messing with."
One of Mayweather's sons saw the fight, ran out of the house, and alerted a friend of his mother's, who called the police, according to the police report.
Harris told Yahoo's Martin Rogers in 2013, "Did he beat me to a pulp? No, but I had bruises on my body and contusions and [a] concussion because the hits were to the back of my head. I believe it was planned to do that … because the bruises don't show …"
Harris had "redness on her face and a large contusion to the right side of her forehead and chin" when she was examined at the hospital, according to the incident report.
Mayweather Promotions did not respond to our requests for comment on this story.
Outside of these three incidents, Mayweather has been accused of domestic violence numerous other times. Deadspin published an exhaustive report of these accusations in 2014. According to their report, Mayweather has been accused of violence against women seven times in the last 13 years, including a 2005 incident where he was found not guilty of battery after Harris recanted an allegation that he hit and kicked her outside a club.
Despite his 2011 guilty plea, Mayweather recently told Yahoo's Katie Couric that he doesn't beat women.
About the Josie Harris incident, he told Couric:
"Did I kick, stomp and beat someone? No, that didn't happen. I look in your face and say, 'No, that didn't happen.' Did I restrain a woman that was on drugs? Yes, I did. So if they say that's domestic violence, then, you know what? I'm guilty. I'm guilty of restraining someone."
Harris has since relocated to California with their three children. She told Rogers, now of USA Today, "I was a battered woman. I felt embarrassed about saying I was a battered woman. I felt shame. I felt like it was my fault. What did I do? I didn't understand what a battered woman was at that time. Now I know I was in a very dysfunctional, hostile relationship and a victim of domestic violence."
Mayweather has avoided the sort of public scorn that high-profile athletes accused of domestic violence have faced. Boxing is a niche sport, and doesn't have the sort of authoritative governing body that can meaningfully punish a figure like Mayweather.
Now, before the rare fight that will draw in non-boxing fans, awareness of Mayweather's domestic violence history is starting to go mainstream.
Pacquiao's trainer Freddie Roach has used Mayweather's history to create a good versus evil narrative around the fight.
"Manny is really against domestic violence," Roach told USA Today. "It is a big issue maybe in the Philippines for him and being a congressman he can control some of that stuff. That is a big plus for me that Manny does not like the guy, I think the killer instinct is going to come back a lot faster."