Floyd Mayweather has issued a low blow with his latest claim that he is better than boxing greats, including Muhammad Ali and Sugar Ray Robinson. 

Barely two weeks before his fight with Manny Pacquiao, touted as the "richest" fight of the millennium because of the prize money involved, Mayweather could not help but boast to ESPN's Stephen A. Smith that no other fighter is better than him.

Mayweather said his 47-0 record says it all and added that no one could convince him that Ali was a better fighter who was defeated by an unworthy opponent, Leon Spinks, with a 7-fight record.

The boxer also downplayed Ali's win against George Foreman, which he called "bush-league."

Sports columnist Skip Bayless said in ESPN's "First Take" that "Mayweather was not just disrespectful (to Muhammad Ali and Sugar Ray) but was flat out blasphemous."

"Mayweather is so full of himself and blatantly scoffed at Ali's accomplishments," Bayless said.  

Global boxing fans maintian that Robinson is the best pound-for-pound boxer, while Ali has been known as the greatest fighter in boxing history, news.com.au said in another report.

Mayweather, who clearly has an advantage in the ring against Filipino boxer Paquiao, is currently preparing for the May 2 fight to be held at the MGM Arena in Las Vegas.