Shavers was a huge hitter like Foreman, but I don't think he'd be able to bull Joe around and push him off like Foreman. This tactic was key to Foreman's destructions of Joe. Joe would get inside and do his thing and stop Shavers in 6 to 8 rounds.
Joe's relenteless style would grind Shavers down the 4th, 5th or 6th round for a KO or stoppage. Joe TKO5.
Shavers best chance is in the first 2 rounds. Earnie starts fast, Frazier starts slow. (Mando Ramos, Quarry, Ali, and others all wobbled Frazier early, plus Big George).
Shavers, Foreman or any other big puncher wouldn't be allowed to push and shove off against Frazier if the referee does his job and keeps the fight under control. Foreman's tactics were illegal in the 1973 fight and Mercante shouldn't have allowed him to continue without a strict warning. Even a depleted Frazier at that time has a better chance of winning if Foreman was forced by the referee to move and box out of the clinches without grabbing his shoulders and shoving him aside illegally. Foreman wasn't a strong inside fighter and Joe would certainly have done more damage if he was actually allowed to fight on the inside. As for a fight between Frazier and Shavers, I'd say Frazier KO's Shavers inside 8 rounds, if not earlier. Shavers wouldn't have been able to handle Joe's pressure and body attack.
It's interesting that both Ali and Foreman had to bend and break the rules to keep Frazier off them. For all their reach advantage, and despite immense power punching (Foreman) and speed and skill (Ali), they couldn't stop Frazier closing on them.
Frazier has a good shot to stop him in the first 2-3 rounds. If it goes past 3 then Frazier takes over and has the win. But those early rounds could be dangerous and anything could happen. My pick would be Frazier KO 8.
This is a good caveat to consider.. Although I'd pick Frazier to win, he did indeed took a bit of time to warm up before getting the better of his prey. In the meantime, he was often outboxed or floored in the early rounds. Shavers was not the fastest starter in the world either - or at least not against world class opposition ( see Jerry Quarry ), however, that right hand often landed early and hard. Joe would have to be cautious early on, but swift as to get the job done soon. I'm not sure that his behavioral patterns warranted it on a historical basis though. Additionally, Shavers was not really viewed as a threat in the early 70's, in fact he was not taken very seriously until he received the testimonies of Ali and Holmes until much later, as one of the deadliest bombers in history. This might be a nasty cocktail for an unsuspecting Frazier in 1973, who possibly may have viewed Shavers as a crude club fighter. Nevertheless, I have to go with Frazier on the basis of proven ability against top raters, as well as Shaver's track record of having a questionable chin and stamina. Frazier would have my vote to win, but make no mistake about it, this would be a very dangerous fight for him. Any outcome is possible. Joe could win this in a single round, or he could struggle with Earnie for several rounds sustaining multiple knockdowns before winning, then again, he could lose altogether. My guess, is Frazier batters Shavers enroute to a mid round TKO, but as I have advocated several times already, anything could happen...
That's why it is a good question ... one guy starts very fast and punches like hell while the other is a slow starter ... I just think Joe would be aware of the power and be careful not to get tagged early ala Norton ... other than that Frazier stops him inside of four or five ...
