From 2008 until 2012, Manny Pacquiao was considered by some fans and media to be the best pound for pound fighter in the world. He was called a legend and the greatest to lace up a pair of gloves since Ray Robinson or Muhammad Ali. There is no doubt that Pacquiao was an outstanding featherweight and junior lightweight.
During his time in those divisions he defeated great fighters like Marco Antonio Barrera, Erik Morales, Juan Manuel Marquez and good contenders like Jorge Solis and Oscar Larios.
However, when his accomplishments from 2008 onwards are studied closely, they do not seem all that impressive.
Bernard Hopkins and James Toney were both middleweight champions in the 1990s although they were never in the same division long enough to be able to face each other. Toney won the title by knocking out the highly regarded Michael Nunn while Hopkins defeated Sergundo Mercado in a rematch to become champion. Hopkins held the title for a decade and made 20 defenses while Toney only stayed around for a few years before moving up to 168lbs. 
The talk in the boxing world is that after Floyd Mayweather defeats his opponent on May 4th in Las Vegas, Nevada, will be facing Saul “Canelo” Alvarez on Mexican Independence Day weekend in September. This would be a huge fight involving two of the biggest pay-per-view stars in boxing and may even break the pay-per-view record currently held by Mayweather and Oscar De La Hoya. But what has Alvarez accomplished in boxing to deserve such a big fight?