A prime Liston would have been very hard to beat. The prime Liston was faster than the Liston of the Ali fights and with his long reach it would be hard to catch him. Plus Ali said that Liston was the most skilled boxer he ever faced, so Liston was also technically a great fighter. The only boxer before the Joe Louis era who would have troubled Liston was James Jeffries. Liston would have destroyed Dempsey, Johnson or Tunney all by KO. They never faced a boxer as strong and as great as Sonny. Johnson would maybe trouble him, but I see Liston knocking him out in the later rounds. Jeffries would be dangerous for Liston because of his speed and strength. Jeffries weighed 220 lbs, but was fast like a light heavyweight. But I still think that Liston would beat Jeffries by points, when he can manage to avoid Jeffries punches and keep him at bay with that damn long reach and dangerous jab(the best jab in boxing history). Joe Louis however would have probably beaten Liston. But Sonny would be extreme dangerous for Louis(more dangerous than everyone Joe has faced in his prime). Sonny would have the power and the skills to knock Louis out, but I think Louis would handle him with his fast hands and great defense skills and wins this one with fight by a split decision, because Louis was the better overall boxer than Sonny. Sonny would then beat every fighter until Larry Holmes(except Ali of course). Larry is very similar in style than Ali and has a comparable jab to Sonnys. So he would be too fast and great for Liston. Plus Larry has a too hard chin for Sonny. He over-lived the shots of Earnie Shavers, so it would be hard for Sonny to KO Larry. After Larry Sonny would beat every heavyweight champion until Vitali Klitschko. Klitschko would trouble Sonny even more than Lennox Lewis, because Lewis has a questionable chin and that-for I see Sonny knocking him out. Tyson would trouble Liston with his speed and punching power, but I don't see Tyson knocking Liston out and running out of gas in the later rounds, which would lead to his loss. Vitali Klitschko would be too tall and strong for Liston. Plus he has a hard chin(Wladimir's chin is weak and thats why he wouldn't last long against Liston). Riddick Bowe is technically too weak for Liston. Vitali Klitschko however is the only boxer I give a chance to knock a prime Liston out. Many see Vitali as a bad fighter, but he has a great defense and would have enough power to knock Liston out. And he's one of the only fighters who would be tall enough to fit Listons reach.

So, Joe Louis, Muhammad Ali, Larry Holmes and Vitali Klitschko are the only heavyweight champions who could've beaten a prime Sonny Liston.

The only two heavyweight champions I give at least a good chance in beating a prime Liston are a prime Mike Tyson and a prime James Jeffries, because of their speed and their punching power and Jeffries toughness.

All other heavyweight champions wouldn't have lasted long against a prime Liston or wouldn't have been great enough in beating him by points.

Oh there are a number of them: Jack Johnson, Joe Louis, Larry Holmes, Lennox Lewis, Evander Holyfield. These guys, like Ali, all got quick hands, smarts, ring savvy and decent power. And they wouldn't be intimidated or scared by Sonny, which is the key to beating a big bully like Liston.

I'd say Joe Louis, definitely. Foreman v Liston would've been an interesting match. I think Liston would've beaten Tyson. Lennox Lewis, maybe. Larry Holmes probably would've taken Liston too.

Based on his record, I think Liston could only be beaten by fighters who are highly mobile defensive and durable master boxers or fighters who could punch as hard or harder and have great stamina.

Given that premise, I think apart from Ali, master boxers like Jack Johnson and Ezzard Charles in their prime could beat Liston and tough, durable boxer-punchers and puncher-boxers as Joe Louis, Rocky Marciano, Joe Frazier, George Foreman, Mike Tyson, Evander Holyfield Riddick Bowe and Lennox Lewis also have a shot to beat him. I think the Klitschko Brothers in their best prime can also beat Liston.

Only a select few. Joe Louis was great, but lets face it, Liston would have hammered him.

hmm, Joe Louis probably could, Jack Johnson probably, Mike Tyson, George Foreman, Joe Frazier, the Klitschko's, and Lennox Lewis, just to name a few.

Frazier, Tyson, ken norton ,foreman and maybe Holmes and Holyfield