Manny Pacquiao (54-3-2, 38 KO), Floyd Mayweather (42-0, 26 KO), Juan Manuel Marquez (53-6-1, 39 KO), Sergio Martinez (48-2-2, 27 KO) and Andre Ward (25-0, 13 KO) share a distinction in boxing.
They are all unanimously featured on every major boxing authority's pound for pound list. From BoxRec to Yahoo! Sports to "the bible of boxing" Ring Magazine, the same athletes are said to be among the best.
Many of these colorful characters on boxing's pound for pound list just so happen to be only one or two weight classes from each other. Some are even (GASP!) in the same division.
While seeing the best fighters take on the contenders of their crowded divisions is always interesting, it's always more intriguing to see the best actually fighting the best.
When Mayweather dominated Shane Mosley (46-7-1, 39 KO) when Mosley was ranked third pound for pound, he first had to survive two hard shots from Mosley's heavy hands in Round 2 that wobbled him.
Martinez's shocking second-round knockout of Paul Williams (40-2, 27 KO) elevated Martinez in the pound for pound rankings. A former staple of pound for pound rankings, Williams exited those same lists.
Pacquiao and Marquez have fought in three heavily debated wars in the ring. The trilogy has helped build their careers, legacies and rankings substantially.
People gather around any pound for pound showdown because the outcomes are never certain when the best face the best. Even when the winner is expected, the path to the results can be unpredictable.
Great fights, moments and victories pave the way toward history. So here are the 10 best pound for pound showdowns that are actually possible in 2012.