In more than one way, George Chuvalo’s life has been an unending and merciless endurance test. A barrel-chested, bulletproof heavyweight with killer instinct and hitting power, he had all the attributes to become a champion, but fate matched him against some of the finest glamour division combatants of all time.

Floyd Patterson, Muhammad Ali, Joe Frazier and George Foreman were all active during Chuvalo’s tenure, and that was only the legendary reigning or future world champions that he had to contend with. Chuvalo also punch-swapped with Zora Folley, Doug Jones, Ernie Terrell, Oscar Bonavena, Buster Mathis, Jerry Quarry and Jimmy Ellis.

Despite being matched tough, the proud Canadian warrior would never dream of complaining. Chuvalo fought and recovered, fought and recovered, fought and recovered in a pattern he was forced to replicate when a horrific war of attrition with family bereavement brought this immensely proud man to his knees.

“I lost my wife [to suicide], three sons [one to suicide and two to drugs], and I lost my granddaughter last year,” Chuvalo told The Ring in 2014. “My granddaughter passed away from cancer. She was a beautiful girl, a schoolteacher, who spoke three languages.

“In many ways, losing her almost sent me over the top. I loved her like crazy, and she had her whole life ahead of her. She was only 30 years old.”

Life did to George Chuvalo what no man ever could — it floored him — but not for a 10-count.

His final ring record was 73-18-2 (64 KOs), and while there were losses that he could have done without, Chuvalo picked up a baseless reputation as a walking punch bag. History tells another story about this remarkable man’s achievements in the ring.

As Chuvalo, then 76, reminisced, I was struck by both his memory for detail and the insurmountable pride which still resides within him.

The Ring spoke to Chuvalo about the best he faced in 10 key categories:

Muhammad Ali: Ali had the best jab, but this area shows the difference between fights one and two. In the rematch, I was able to use my jab against him and had real success with it. [Angelo] Dundee said he was surprised I stopped throwing it in the second half of the fight because I was matching Ali at times. The jab is important and sets up all your other shots, but I didn’t use mine as much as Muhammad used his. Watch the rematch again and you’ll see I was successful with mine early.”

Joe Frazier: “Joe Frazier, believe it or not. He was very hard to hit because bobbing and weaving was natural to him. He’s recognized as a great fighter, but not many people compliment Joe on his defense. The uppercut was the only shot he was really susceptible to, as we saw against George Foreman. Joe was excellent at avoiding straight punches, which was the reason he gave Ali so much trouble in the first fight. He slipped the punches and closed the gap.”

Ali: His jab was quicker than any punch I ever came across. Floyd Patterson is a close second, but Ali definitely edges him in terms of hand speed. Floyd and I fought The Ring Magazine Fight of the Year in 1965, which was kind of cool at the time. It was close and could have gone either way, but Patterson was a New Yorker and we were fighting at Madison Square Garden. I wasn’t surprised that he got the decision.

Hector Eduardo Corletti: He ran around like he was on a motorcycle that night in London. I was actually laughing because he was jumping around all over the place and it was funny to watch. The irony is he ran like hell against me, but traded punches with Jerry Quarry and Al "Blue" Lewis and got himself knocked out.

They gave Corletti the decision against me, even though I busted his cheekbone and shook him up pretty good. The thing is, in England they didn’t encourage in-fighting, almost to the point where they don’t allow it, and that prevented me from producing my best work. I wish I could get myself a copy of that fight, because I haven’t seen it since 1966.

Ali: Whenever he was hurt, he faked his way out of it and that came with experience. Despite all of his attributes as a fighter, he survived so many rough moments by being a great bluffer. He was tough to hit, and when you eventually did get to him, he outsmarted you, and that might have been your only chance. He had so many tricks up his sleeve.

George Foreman: We didn’t find out if he could have maintained that strength. Honest to God, I think I had him. George was winded at the end [in Round 3], breathing very heavily, and my ability to take a good whack was never questioned, whereas Foreman’s stamina was. Later, Ali exploited George’s weakness in a spectacular con job, but, in terms of intelligence, The Rumble in the Jungle was the best fight I ever saw.

Ali: According to Angelo Dundee, I had him out in Round 5 of the rematch, but he bluffed his way out of it and waved me in. I clipped him with a left hook to the point of the chin and it was perfectly placed. He did the same thing with Earnie Shavers a few years later. Still, over the 27 rounds we fought, his chin was definitely the most reliable.

Foreman: He was very heavy-handed, and there was a different feel to his shots. Joe Frazier and Jerry Quarry hitting you was like being struck by a car at 100 miles per hour, but when George landed it was like being hit by a Mack Truck at 50 miles per hour. There was more weight in his punches. Still, I was upset that the referee stopped that fight because I was fine, and Foreman was getting tired. He was exhausted, and I honestly believe I would have knocked him out had I been allowed to continue. Look what happened to him in Zaire four years later.

Mike DeJohn, when he was on his feet, was a sharp puncher with a good uppercut, but the referee helped Mike out more than once.

Ali: Ali in the first fight. I tried to apply pressure and take him to the ropes because he was so dangerous at long range. The trick for me was to keep it close and punish him heavily to the body. Before the rematch in Vancouver, Ali asked my trainer if we were planning on going to his body again, so it was on his mind. After our first fight, Ali was taken to St. Michael’s Hospital in Toronto with bleeding kidneys, whereas I went dancing with my wife.

Ali: Ali in 1966. Although his quickness was outstanding, he was able to absorb a great shot and tricked you in the ring. You could hurt Ali and never know it. By his own admission, I had him in trouble once or twice, but I didn’t take advantage. I only had 17 days' notice for that fight, and if I’d had an extra month of preparation, then that would have helped me a lot.

When Ali and I met again, in 1972, he wasn’t the same fighter. There were a few sports writers who actually thought I won the rematch, but when I tell that story now, people laugh. In the second fight, his speed and skills had diminished slightly, and he wasn’t as consistent with his work.