While Amir Khan has the biggest name of any opponent in the mix to face Floyd Mayweather Jr. besides Manny Pacquiao, some have pointed out glaring blemishes on Khan's record. The biggest black mark against Khan is a 2012 TKO against Danny Garcia, the top 140-lb. fighter in boxing with an undefeated record.

Khan has claimed his fast hands and boxing ability are the remedy to solving Mayweather's defensive puzzle, but Mayweather apparently thinks he needs to beef up his resume some more.

"He [Khan] still got Danny Garcia problems and there's another guy over in the UK. No, not Kell Brook. Kell Brook is a good, little fighter. I was impressed. I'm talking about another guy that slept Amir Khan," Mayweather told Fighthype.com.

The "other guy" Mayweather is referring to is Breidis Prescott, who dropped Khan in Round 1 of a 2008 bout. Those two fights have created a perception of Khan as having a "glass jaw," and even though he's won his last three fights that image persists.

While Khan does have these issues with his candidacy for a Mayweather fight, there aren't many other names on the horizon to intrigue the boxing public. Garcia's never fought above 140 lbs., and he has a unification bout with Lamont Peterson or a rematch with Lucas Matthysse available to him as options for his next bout.

Mayweather could of course set aside his differences with Top Rank CEO Bob Arum and stage a fight vs. Pacquiao, but the latter must first win his November 22 fight against Chris Algieri.

Aside from Khan or Pacquiao, the only other conceivable fight would be a rematch of Mayweather's 2012 fight against Miguel Cotto, who is now the WBC middleweight champion. Catchweights could be an issue now though. Mayweather's been fighting consistently at welterweight, which may be a long way down for Cotto even if he's a small middleweight.