By Edward Chaykovsky

Former two division world champion Paulie Malignaggi has tabbed fighters like Keith Thurman and Amir Khan as posing the biggest risk for the perfect record of WBA/WBC 147 & 154-pound champion Floyd Mayweather Jr. (47-0, 26KOs).

The biggest fight in boxing is still a battle between Mayweather and WBO champion Manny Pacquiao. Malignaggi sees Mayweather beating Pacquiao quite easily, but says Khan and Thurman would be tougher challenges for the pound-for-pound king.

"A really intelligent boxing fan would understand that people like Keith Thurman and Amir Khan are more dangerous to Floyd Mayweather than Manny Pacquiao at this level, at this point," Malignaggi told ESPN.

"For the mainstream sports fans that don't really understand boxing the way they should then the Mayweather- Pacquiao fight will always be the intriguing fight that never happened so if it can happen then it will generate a ton of interest, a ton of worldwide audience.

"But I actually think it's a pretty easy fight for Floyd Mayweather to win and I think guys like Khan and Keith Thurman would really, really risk..pose a big risk to the perfect record of Floyd Mayweather."