LAS VEGAS -- Perhaps it was only a small window into how jail might have changed pound-for-pound king Floyd Mayweather Jr., but it was noticeable. There was a new sense of calm and serenity that seemed to surround him like never before.
At Wednesday's final news conference ahead of Mayweather's welterweight title defense against interim titleholder Robert Guerrero, Ruben Guerrero -- Robert's outspoken father and trainer -- launched into an unprovoked attack against Mayweather when it was the elder Guerrero's turn to speak.
In the most memorable moment from an otherwise cookie-cutter media event promoting the fight Saturday night (9 ET, Showtime PPV) at the MGM Grand Garden Arena, Ruben Guerrero began shouting at Mayweather.
"We're going to beat up that woman-beater -- the one that beat up his wife," Guerrero yelled. "He beat up his wife in front of his kids! He must have learned that from his dad. We're going to beat that woman-beater!"
Guerrero was, of course, making reference to Mayweather's guilty plea to domestic abuse charges that landed him in the Clark County Detention Center for two months this past summer. He was released a month ahead of schedule for good behavior, but, in layman's terms, Mayweather was locked up for the 2010 assault of Josie Harris, the mother of two of his children, who witnessed the incident.
The Mayweather of past years might have retaliated at Guerrero, launching his own verbal assault. Things could have gotten really ugly.
But on this day, the star of the show -- one year removed from his points win against Miguel Cotto to capture a second junior middleweight belt -- sat quietly without saying a word. Later, Mayweather said he was texting with his girlfriend and ignoring Guerrero.
"I don't have to fight his father," Mayweather said. "I'm there to fight the fighter. I'm a lot older now, so I'm a lot wiser. When I was young, you seen a wild Floyd Mayweather, but I'm a lot older now. My kids are teenagers now. So I can't be conducting myself in a disorderly fashion.
"I love my children and I have nothing negative to say about the mother of my children. Only God can judge me.
"I'll just say a prayer for him," Mayweather said of the elder Guerrero. "I'm not upset at all. I just keep my composure."
The time in jail, it seems, has mellowed Mayweather, at least outside the ring. Perhaps he looks back on those 64 days of incarceration -- all of which were done in solitary confinement, for his own protection, according to jail officials -- as the seminal time of his life.
Clearly, based on Mayweather's attitude and the way he has been discussing his time away, he learned a valuable lesson and has no intention of going back.
"I was thankful for everyone that wrote me letters and the fans that wrote me," Mayweather said. "I was thinking like, man, money don't define who I am. I make money, money don't make me. I'd rather have my freedom and be poor than be rich and don't have freedom. I said [to myself while in jail], 'You know what, I want to grow closer to my family, do things a lot different now.'"
Part of that, he said, is how he tries to teach his kids.
"I look at my boys and I tell them what you see on rap videos, sagging your pants, is not cool," he said. "Piercing your ears is not cool. Just teaching them different things -- always have manners, always be respectful, always be appreciative and thankful for what you do have. I think about that stuff every day."
Because Mayweather was in solitary confinement during his term, he spent 23 hours a day in his cell, with one hour a day for recreation by himself.
For somebody as active as Mayweather -- it's normal for him to go out for a run at 3 a.m. or to hit the gym at some other odd hour -- that was difficult.
"The situation I went through, if I was in general population, then it would have been a little different, to where you got to communication with other humans -- y'all talk, y'all communicate, you're doing certain things, you're playing certain games, y'all playing basketball," Mayweather said. "But I did my whole time in administrative segregation.
"I was with the worst of the worst. There was a story about a guy who chopped people up with an ax. On weekends, you can't come out, so out of a whole week you come out of your cell five hours. I learned a lot just sitting and talking to my lawyer every day. I can't surround myself with people who are going to put me in a tough predicament."
Shane Emrick, one of Mayweather's attorneys -- who has grown close to him -- said that Mayweather was "treated differently because he's Floyd Mayweather. He's the only person in the last 25 years that served a misdemeanor conviction in solitary confinement, maximum security."
Mayweather said he passed the time exercising as best as he could in cramped quarters and reading.
"Reading books and doing pushups," Mayweather said. "That's all I could do. I wasn't reading nothing that's negative because you're already in a negative environment. You don't come in contact with no other inmates.
"It's crazy that you may know everybody in all the cells but you never touched nobody's hand, never shook hands. It was a wild situation, but I'm thankful I'm home and able to spend time with my family, and I've come to find out there's nothing more important than freedom."
He said he got thousands of letters from fans, which helped keep him going.
"They were getting upset, saying I was getting too much mail," he said of the jail officials. "I love my fans. They were very, very supportive. Even if somebody took time out to make a negative comment, they took their time out of their life to write about me. Whether it's positive or negative, thank you. I had your attention at that particular time."
When Mayweather was released, he made some major changes in terms of his boxing business. For one thing, he asked his father, Floyd Mayweather Sr., to return as his head trainer. They had spent years estranged, and Mayweather Sr. had not been in his son's corner in 13 years.
In another major move, Mayweather cut ties with HBO, the network he had been with for virtually his entire career, to sign a six-fight, 30-month deal worth an estimated $200 million-plus with Showtime/CBS.
Whether those changes have anything to do with his mindset coming out of jail and his desire for security is unclear, but there seems to be a clear change in him.
"He's a lot more laid-back, and he values freedom," said adviser Leonard Ellerbe, the CEO of Mayweather Promotions. "Having been incarcerated was definitely a life-changing experience for him. It was something he hadn't experienced before.
"No one wants to be in that situation. There's nothing to prepare you for something like that. The environment and conditions he was placed in made it tough. But that's behind him. He did his time, and it's time to move on."
Mayweather Sr., who served time in prison for drug trafficking, said he has noticed a change in his son.
"It seems like he's changed for the best," he said. "I can't say how nobody is going to be, how nobody is, but so far it's been good. I just think he's much better all the way around, to me. He's more calm. It seems like he's more productive. He's more pleasant to talk to, not that he was ever that bad talking with me anyway.
"I would have to say it changed a lot of things. If he was still in the same position [of having not gone to jail], I don't think he would have called me to camp."
Golden Boy chief executive Richard Schaefer, who is promoting his seventh consecutive Mayweather fight, also has noticed changes in Mayweather.
"I think [there are] certain things you take for granted that he doesn't take for granted anymore, and I think freedom is one of them," Schaefer said. "I think [going to jail] might have changed his values a bit. When you look at another fighter who was in jail and came out and changed his life around, obviously, you talk about Bernard Hopkins [who did 4½ in years in prison for armed robbery]. There are very few interviews you have with Bernard where it doesn't come back to his time in prison.
"It's different circumstances, but the fact that Floyd was in [jail], it does change you. You realize, 'I don't like that.' And it's in his hands and his control to ensure it doesn't happen again. Maybe it had something to do with him embracing his father again. I can't speak for him, but I can see a difference. I think the [Showtime] deal had to do with it, as well. You realize how precious life is and how quickly somebody can throw you a curveball, and I think he realizes he is towards the end of his career, and when you do spend that time by yourself in that little cell, you start thinking about things."
Whatever Mayweather thought about while he was jailed, he seems at ease now. Maybe it's the kinder, gentler Mayweather -- outside the ring, at least.
"I feel like me being incarcerated was just an obstacle, something that's in your way," Mayweather said. "It was a minor setback for a major comeback. So things happen, but you know, when it's all said and done, only God can judge me. I think that everybody goes through ups and downs. I don't think nobody has a perfect life. So that just happened to be a part of my life. The only thing that I can do is to take the good with the good and the bad with the bad.
"The only thing you can do when you're locked up is just do pushups and read and write, write your fans and write to your loved ones. That's all I really did. So I think what I thought about every day [was] my children. I thought about my family. Of course, I thought about my career, and I'm happy to be home."