Mayweather prepares for Guerrero bout following eight-weeks of horror in prison

On Saturday night it will be one year all but a day since Floyd Mayweather's last fight. That is a long time in boxing, especially for a man in his 37th year, but it is not age or ring rust which will nag at the best fighter in the world as he climbs through the ropes at a packed and pulsating MGM Grand Garden Arena.

Nor is it an opponent, Robert Guerrero, who is a six-time world champion in his own right.

Head to head: Floyd Mayweather and Robert Guerrero

It is that brief but infamous eight-week spell in the midst of these 12 months which Mayweather will carry with him into this defence of his world welterweight title.

By extraordinary coincidence, he comes back from that jail term as the 44th opponent of his unbeaten career is facing the likelihood of prison on a gun charge. So perhaps it not entirely by chance that Mayweather has chosen this moment to plant in Guerrero's mind the privations which await him in the penitentiary.

The Money man's credo whenever he prepares to do business in the ring is this: Hard Work – Dedication.

When he went inside for assaulting the mother of his children it changed to this: Maximum Security – Solitary Confinement.

As he returns to work, Mayweather has given a revealing insight into the rigours of prison in the desert state of Nevada. His jail stands but a short drive from the Las Vegas Strip in all its crowded glamour but none of the clattering sounds of the casino reached his cell.

Floyd Mayweather Jr. (L) and Robert Guerrero

'I was locked in a silent room for 23 hours a day,' he says. 'Twenty-four hours a day at weekends. I was in the high security section of 34 cells mostly occupied by the worst in the world. There were murderers there on Death Row.

'I was in solitary confinement (the authorities said for his own safety as a celebrity) and for the one hour a day I was allowed out to exercise I was still by myself.

'The only conversations I had with any other inmates were short and shouted through the doors when I was walked back down the corridor. Sometimes I could hear a couple of them working. They were making chess pieces. But there was no real contact.

'All that got me through it (the loneliness) was that my lawyer was allowed to visit me most every day because we had to discuss other legal matters.

'Then I noticed my shirt getting tight. My body was getting bigger just sitting there reading magazines.' For an athlete who prides himself on keeping in prime physical condition, this was a crisis: 'There wasn't much room so I started doing push-ups. Maybe a couple of hundred the first day, then hundreds and hundreds every day. Push-ups hour after hour.

Flashpoint: Mayweather refused to respond when 30-year-old Guerrero¿s volatile trainer-father screamed at him that he is a 'wife-beater'

'But I learned something in there. I learned that freedom is the most important thing. Freedom to spend time with your children. Freedom to pursue your career. Freedom to live your life. Freedom to do what you choose. I thought about that every day. And all I did every day apart from push-ups was write to my loved ones, write back to my fans. 'I'm happy to be home and I'm never going back.'

Most fighters who go to prison, even for a short time, are not the same when they come out. The experience changes most men, and women.

Mayweather does not seem to sense any significant difference in himself, yet he does conduct himself now with more maturity. The celebrity lifestyle may still be extravagant but he is more thoughtful and reflective in conversation than he used to be.

His temper is more restrained. So he refused to respond when Guerrero's volatile trainer-father screamed at him that he is a 'wife-beater' when the two teams came face to face at the final pre-fight press conference. Nor has he reacted, at least not thus far, to an interview just given by that ex-girlfriend in which she refuted his under-stated version of that domestic incident which put him behind bars.

After the Guerreros ranted about how Robert The Ghost is going to end his perfect record, Mayweather said quietly: 'All I can be is the best I can.'

Boxer Robert Guerrero speaks onstage during the final news conference for his bout against Floyd Mayweather Jr

Boxer Robert Guerrero speaks onstage during the final news conference for his bout against Floyd Mayweather Jr

More privately, he expressed his happiness that Guerrero's wife appears to have won her battle with life-threatening leukaemia. Although he did add that he finds some of the behaviour of his challenger a mite hypocritical for a devout Christian.

Has prison changed Mayweather? If so, it appears to be for the better.

The angry young man who emerged from poverty on the mean streets of urban America brandishing his new-found fortune under everyone's noses in the form of wads of money seems to have found his dignity in the most humbling of places.

Mayweather Vs Gurrero fight will be live on Supersports 2A from 21:00 CAT