When does he suffer his 1st loss? 2nd loss? Going by this timeline? Does he even lose that many? Can he go undefeated? 64-65 Patterson/Liston Version of Ali vs 1992 Prime Riddick Bowe 1992 Lennox Lewis of Ruddock Fight 66-67 Chuavalo/Williams/Terrell Version of Ali vs Prime Michael Moorer Old George Foreman Prime Ray Mercer 70/71 Quarry/Joe Frazier I Version of Ali Mid 90's Holyfield of Mercer/Czyz/Tyson Fights Lennox Lewis of Briggs/Golota Fights. 1974/75 Version of Ali from Foreman/Frazier III vs Wladimir of the early 2000's. Byrd I, Mccline fights Lewis of Grant/Tua/Botha Fights Vitali of Lewis Fight/Williams/Johnson Fights 1977 Shavers Version of Ali vs Roy Jones Jr from Ruiz Fight James Toney at HW Sam Peter from Wlad I/Toney Fights
It's only really post-exile version of Ali I could see losing here. Lewis would have been a handful for any version of Ali. As for the likes of Jones, Toney, and Peter, they wouldn't have even beaten a faded version.
I'm going to 'split hairs' a bit here. The Ali of the Foreman fight would beat any version of Lewis,imo. Best incarnation of Lennox MAY have been able to have got a close decision over the 'Thrilla in Manilla' version.