Ali easily.. I think he fought the best competition of any fighter, and also IMO is probably who I consider as much a contender for best fighter p4p as Ray Robinson... he beat Fraizer, Foreman, Shavers, Norton, Liston, Jimmy Young, Ron Lyle, Patterson, Chuvalo, Quartey, Ellis, Archie Moore, Karl Mildenberger, Cleveland Williams, Ernie Terrell.