LAS VEGAS – Floyd Mayweather believes the key to his hard-fought victory over Miguel Cotto on Saturday night stemmed from the night he shunned a trip to an Orlando strip club and went for a six-mile run at 3a.m.

Mayweather defeated Cotto by unanimous decision following an arduous battle that left him with a bloodied nose and mouth. He was forced to rely on the stamina built up during a grueling training camp.

That camp was scheduled to begin at the start of March but instead Mayweather opted to start his preparations a week earlier in the middle of the night during NBA All-Star weekend.

50 Cent, Mayweather's rapper friend and business partner, told how the boxer cancelled plans to head to a nearby night spot and embarked upon a spur-of-the-moment run.

"He did six miles that night," 50 Cent said to Y! Sports. "I thought he was crazy. I thought he was joking. I have never before just seen a person start randomly training like that. We were so far away from the gym, we weren't even close. Before that, we were going to a strip club.

"That is what he is all about, working hard and showing that kind of extreme work ethic no one else has. He showed a lot of spirit and determination. Everyone understands what it takes to be successful but he does it better than anyone."

[ Kevin Iole: Floyd Mayweather Jr. bloodied but still perfect after Miguel Cotto fight]

Cotto came to fight at the MGM Grand Garden, attacking Mayweather and landing heavy blows with both fists. The Puerto Rican busted Mayweather's nose and lip during the middle rounds and deserved better than the judges' scorecards of 117-111, 117-111 and 118-110.

Mayweather's stamina has rarely been tested as strongly as it was on this night and the 35-year-old pound-for-pound king took well over an hour to appear for his post-fight press conference as he mixed celebrations with receiving treatment for his wounds.

But he traced his eventual success to that night in Orlando and the base of endurance he built up over the course of a camp that spanned more than two months.

"The first day back I ran six miles," Mayweather said. "I hadn't done anything for nine months and I just went out and ran six miles. Cotto had fought not that long ago, so I had to get my endurance in. Training camp started right then. I was running a lot, 5:45 or 6:00 minute miles. It all set me up."

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Mayweather is headed to Clark County Detention Center for an 87-day jail stint on June 1 and the physical punishment he received from Cotto may mean he does not fight again this year. He even hinted he could walk away from the sport, but given his love of attention and multi-million dollar paychecks, that must be considered unlikely.

He did, however, insist that boxing's dream bout between himself and Manny Pacquiao was doomed to go down in history as perhaps the sport's greatest "what if."

"The Pacquiao fight is not going to happen," said Mayweather, who cited the Filipino superstar's financial demands, disputes over the style of random drug testing and clashes with Pacquiao's promoter Bob Arum as the reasons for the impasse. "I don't have a boss. I called him direct. I offered him $40 million straight. I told him I would wire him $20 million within 48 hours. But it is not going to happen. There is too much standing in the way. He keeps changing it."

That all remains to be seen, but if a bout with Pacquiao is ever scheduled, there's no doubt Mayweather would be serious about his training – even if it begins on a whim in the middle of the night.

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