The great boxer Kostya Tszyu turns 55 today, and the former pound-for-pound king has many great fights and nights behind him that are worth remembering.

Think of Tszyu, and you’ll likely immediately think of two of his fights: the huge, upset loss to Ricky Hatton toward the end of Tszyu’s career, and Zab Judah, whom Tszyu met when he was in his prime. Tszyu, who has gigantic wins over the likes of Juan Laporte, Sammy Fuentes, Livingston Bramble, Jake Rodriguez, Roger Mayweather, Calvin Grove, Rafael Ruelas, Diosbelys Hurtado, Miguel Angel Gonzalez, Julio Cesar Chavez (a fight the aging Chavez should never have taken), Sharmaba Mitchell, Oktay Urkal, Ben Tackie and Jesse James Leija — went up in flames when he ran into Judah in November 2001.

Tszyu’s stunning, sensational, and even disturbing KO over Zab remains a YouTube favorite.

Why?

If you ever wanted to see what could happen to a fighter’s balance, his ability to think clearly, after taking a single perfectly placed punch to a vulnerable spot on the head—whether it’s the chin or the temple—the brief but highly memorable fight on November 3, 2001 between Tszyu and Judah provides one graphic illustration of that fact.

The two 140-pound contenders met in a three-belt unification bout, and the experts were almost split on who would win. It was a great matchup between two top fighters. Slick southpaw Judah of Modern York was undefeated at 27-0 and held the IBF belt. Tszyu of Australia was 27-1, coming off a loss to Vince Phillips in 1997, and held the WBC and WBA titles.

Instead of a great fight, we got a great KO. A completely devastating knockout that landed the loser in all sorts of trouble.

Zab won the first round, his speed and accuracy admirable, and some fans were already wondering if Tszyu wasn’t just too snail-paced to compete with “Super Judah.” And then, in the final seconds of the second round, it happened. Tszyu landed a perfect right hand to Judah’s exposed chin, a powerful blow that knocked Zab tough onto his back. Judah got up quickly, too quickly, and almost immediately fell back down after trying to talk to referee Jay Nady.

Nady waved the fight to an end immediately after the second knockdown, seeing Judah’s legs completely gone from close range. Judah was inconsolable, crying that it was okay to continue, then he got nasty, grabbing the third man by the throat with his gloved fist, then throwing a stool at Nady. It was an ugly thing. One punch, one perfectly executed punch, ruined the great fighter to the point that Judah didn’t know what he was doing or where he was.

In many ways, Judah’s career never recovered. Tszyu’s punch grenade exploded and Judah suffered the humiliating KO defeat that all fighters fear. Judah fell victim to all sorts of cruel jokes at his expense, with fans calling his “chicken dance.”

All fighters put their lives on the line every time they bravely stepped into the ring. Kostya Tszyu’s brutal knockout proved that many years ago.

Content birthday, champ!

As the scribes wrote at the time, Felix and Oscar were not an “odd couple.” But after Felix Trinidad and Oscar De La Hoya fought 12 rounds at Mandalay Bay in Las Vegas, much was written about how strange the scorecards were. To this day, a quarter-century after the hugely hyped welterweight unification fight, fans argue over who actually won, with some saying De La Hoya was simply robbed on the night of September 18, 1999.

Coming into the superfight, Mexican-American star De La Hoya was 31-0 (25), in excellent shape, and “The Golden Boy” was the current WBC welterweight champion. Puerto Rican superstar Trinidad was also in excellent shape, also undefeated at 35-0 (30) and the reigning IBF 147-pound champion. This was a true pick ’em fight, and fight fans, pundits, and historians were expecting a classic battle.

Instead, we have a chess match. Both men were cautious from the start, with De La Hoya gaining the upper hand with some clever boxing. This was not the Hagler-Hearns crisis some had expected and hoped for. De La Hoya controlled the match, racking up the points, and Trinidad grew increasingly frustrated as he received a real lesson in boxing. It could be argued that De La Hoya deserved to take all nine rounds of the fight. De La Hoya certainly felt he had the upper hand, but as we later learned, it was close after nine rounds – one judge had it 86-86, while the other two had Oscar ahead by a narrow margin, 87-84 and 86-85.

De La Hoya then stopped fighting and threw punches, trying to box to the finish. Trinidad came in sturdy, winning the last three rounds of the fight. De La Hoya was later criticized for “running” in the championship rounds. But De La Hoya felt he had done enough, so why mix it up with a risky banger like Trinidad and risk getting tagged when he tired?

At the bell, both declared victory, but the decision, the majority decision, was Tito’s. The scores of 115-113, 115-114, 114-114 remain hotly debated to this day. Mike Tyson said at the time that “that decision stinks,” and Tyson, along with many others, felt that De La Hoya had been robbed of his belt and his undefeated record. Interestingly, there would be no rematch.

De La Hoya collapsed after a close loss, and his mood only worsened by the insults he received from most of the media. This fight is not as talked about and debated as the Sugar Ray Leonard vs. Marvelous Marvin Hagler fight and its split decision that was divisive, but damn, it’s pretty close.

So many years have passed and who do you think won the Trinidad-De La Hoya fight?

According to many fight fans and historians, the man who gave the incomparably tough Rocky Marciano his hardest night of work was the uncrowned (175-pound) airy heavyweight Ezzard Charles. In fact, the “Cincinnati Cobra” went to war with Marciano twice.

For the first time, in June 1954, at Yankee Stadium in the heart of Up-to-date York City, the 32-year-old Charles gave Rocky, 29, everything he could handle for a full 15 rounds.

For some, it was one of the greatest and most intense world heavyweight title fights of all time. Marciano hit Charles with everything he had, but the older, lighter man took it. And boy, did he give anything in return.

Marciano bled during the fight, and in the first quarter of the brutal fight, a two-inch gash opened up over his left eye. But Rocky simply fought harder when he was bleeding or hurt.

The narrow decision win for Marciano angered Charles and left Rocky unsatisfied. “He deserves a rematch and he can have it,” Marciano said. And fight fans everywhere were certainly eager to see a sequel. There was no ducking or ducking, and the rematch came quickly, just three months later. And more blood was shed in the second battle.

Both greats met in the same place and what happened next became the stuff of legend.

Charles, older and heavier (the latter intentional, the former inevitable), went straight for the champion, his plan seemingly to go for a surprise, quick KO. Rocky ate what was thrown at him, then delivered, knocking out his opponent in the second round. Marciano himself had a momentary mental block, but Ezzard was too slippery, too charming, too challenging to nail. The fight actually became a bit dull (see technicality – not what paying fans expected from a Marciano fight, although Rocky’s legendary fouling ability kept it engaging). Then, in the sixth round, Marciano emerged from the clinch with a dim, deep, bleeding nose injury.

Was that a punch that cut Rocky? Was that the butt? Was that the elbow?

Rocky was fixed by the seventh; indeed, a patch of sorts had been placed on the heavyweight champion’s nose. Charles, now aiming for Rocky’s damaged beak, soon knocked the stain off by trying to do the same to Rocky’s trumpet. The fight continued, and Marciano was bleeding. Today, the fight would have been stopped altogether, and this was the fifties. And this was Rocky Marciano.

In the eighth round, the great fighter cemented his place, his legend and his unique personality in all the significant books. No one can know what pain Rocky was feeling or what the sickening taste of his own blood did to him – but “The Rock” ignored all that and poured it out. His corner told Marciano to go after Charles’ body, and Rocky ran up anyway. His left nostril burst in a terrible way, and his title was in a more threatening position than ever before; Marciano struck with both hands.

The club hit Charles square in the head. Showing incredible courage and bravery in a fight full of both situations, Charles stood up. But Marciano, along with a nosebleed, had the taste of blood in his mouth; he could smell victory. In the final action, Charles knocked Charles down again, and the challenger was on his knees and had no choice but to start the count. The fight was over. Marciano managed to keep his crown with one of the most amazing displays of courage, bravery and never giving up.

Twice in a row Charles came this close to winning the title and setting the record for an undefeated man who had never lost a single title. Twice Charles came this close to becoming a two-time heavyweight champion, and he reigned from 1949 to 1951. Marciano was now 2-0 on Charles, yet both men held each other in undying respect. And in undying respect and appreciation for all fight fans. Both men were truly exceptional fighters. And yes, that is an understatement.