Williams wouldn't beat any top heavyweight out there, he's already shown he isn't world class, and is now past his "best"

He scraped a SD against Audley in a borefest (Guinn then comprehensively beats Audley) and a SD against Skelton in a fouling mess of a fight - Skelton wouldn't beat anyone in world class either, he admits himself how limited his boxing ability is

The only reason they are shouting world title challenge around him is they can make the fight with Valuev and believe he's a soft touch....