Floyd Mayweather
Floyd Mayweather will fight again on Sept. 13. Reuters

Over 18 years, Floyd Mayweather has overcome every challenge that’s comes his way, winning the first 46 fights of his career. As he prepares for his next bout and looks towards possible retirement at the end of 2015, the boxer remains at the top of the sport with no close No.2 in sight.

It’d be impossible to pinpoint just one reason why Mayweather has been so successful. His skills in the ring and his work ethic in the gym have made him one of the best of all time. The veteran has climbed the ranks from featherweight to light middleweight without any difficulty, and has dominated the competition in the process.

How Mayweather has reached such a status has been different than other fighters in his weight class. Mayweather hasn’t made his name as a power puncher, but as a defensive specialist. Much like Pernell Whitaker, Mayweather’s success has been predicated on his ability to avoid getting hit. His agility and smarts have helped him dodge punches, never giving his opponents much of a chance to find a rhythm. Mayweather has recorded just one knockout in his last seven bouts, but he’s won them all in convincing fashion.

"He makes you miss a lot in his fights," former world champion Paulie Malignaggi told Yahoo! Sports last year. "But he doesn't make you miss the same way. If he made you miss the same way all the time, guys would start timing it and start hitting him.”

Not only does Mayweather’s defense help him win individual fights, but it’s prolonged his career. At 37 years old, Mayweather is able to fight with the same tenacity that he did a decade ago by avoiding any major injuries. In his last three fights, Mayweather has gotten by boxers who are an average eight years his junior, and he doesn’t appear to be slowing down at all.

Mayweather’s defense is so strong that his offense might be considered under-rated. He isn't the biggest power puncher in boxing, but he can still hit hard and connect at a high rate. According to CompuBox, Mayweather has landed over 50 percent of his power punches in his last three fights. Twenty-six of his victories have come by knockout.

If it weren’t for Mayweather’s drive and dedication, his skillset wouldn’t be so complete at this stage in his life. As the sport’s top attraction for so many years, Mayweather constantly has a target on his back, with each opponent trying to become the first to end his undefeated streak. It takes a special fighter to withstand that kind of pressure.

At 46-0, Mayweather is just three victories away from tying famed heavyweight Rocky Marciano’s iconic 49-0 mark. He’s avoided losing by not just outboxing his opponents, but by being absolutely dominant. Only three of Mayweather’s decisions have not been unanimous, including his 2013 victory over Canelo Alvarez, which appeared to be as one-sided of a fight as it gets. He had other strong showings against Miguel Cotto and Juan Manuel Marquez, both victories coming by unanimous decision.

In one month, Mayweather will once again put his perfect record on the line, as he faces off with Marcos Maidana in a rematch of their May 3 fight.