Chris Byrd refers to himself as the test, and says nobody wants to study for the test. "It's too difficult." Not many fighters have ever spoken truer words! As a fighter Byrd is basically vulnerable to two things. One is due to his style, being that he is a boxer. The other is due to his size and relatively short reach for a heavyweight. First and foremost, Byrd is a boxer. Boxers are vulnerable to the swarming/pressure style fighters like Marciano and Frazier.
Swarming/pressure style fighters usually cause the boxer problems because they don't allow the boxers to use the ring and box. They try and force them to fight. Former heavyweight champion "Smokin" Joe Frazier molded the pattern on how to fight a mover and boxer. All one has to do is watch any one of his three fights against Muhammad Ali to see just how Frazier gave Ali fits. What Frazier did was take away the space and distance that Ali wanted to box, and forced him to fight. Frazier also started most of his offensive assaults by going to the body first, and then working his way up to Ali's head. His whole fight plan was predicated on not allowing Ali to box and forcing him to fight. If Ali didn't have a cast-iron chin, along with unbelievable stamina and endurance, he would have gone 0-3 vs Frazier.
Byrd, although a southpaw, gains the advantage over his opponents in some ways similar to Ali . What Byrd does is he gives his opponents the illusion that he's right there in front of them. In doing this he wants them to lead off with punches to his head. Due to his head usually being back and away, and his terrific instincts and reflexes, he consistently makes his opponents miss. This is what he wants because after they miss him they are wide open. After they miss he counters them with very quick three and four punch flurries. This pattern is repeated throughout the fight, usually leading to a points win, or a late round stoppage due to an accumulation of punches.
The reason why a swarmer would be effective versus Byrd is because they come in low and go to the body. The swarmer wouldn't fall victim to Byrd's antics of suckering them to go to the head with their lead punches so he can counter them. In his fight against Byrd, Ibeabuchi went to the body early in the fight while cutting off the ring. What this did was slow Byrd which forced him to fight Ibeabuchi instead of boxing him. Once Byrd was slowed to a walk and couldn't get away or hold Ibeabuchi off, the end was a foregone conclusion.
As stated earlier, the style Byrd is vulnerable to is a pressure fighter. This is why I believe that when Tyson was still on his game he would've beat Byrd. Due to his short reach, Byrd is also vulnerable to a tall heavyweight who has a good jab with some pop. Remember, Byrd is strictly a boxer, he is most effective when there is some distance between him and his opponent. This is why it's doubtful that he could beat Lewis or either Klitschko in a rematch? He can't win at long ranges versus either of them.
The problem Byrd would face against them is that they wouldn't have to reach and lunge to hit him. Being that their reach is much longer than his enables them to dictate to him without being countered. Byrd would not be able to counter them because their jabs would keep him off balance. With Byrd not being able to counter, he wouldn't be able to score or land any clean punches.
This would force Byrd to adopt one of two strategies. One of them would be not to change and hope to get lucky and land a big counter punch off a miss and score a knockout. Since he is not a one punch banger, this strategy would certainly lead to defeat. The other scenario would be for him to go to them to try and score. However, this would play right into what either Lewis or the Klitschko's would want.
The ideal situation for them would be for Byrd to come at them. This would make him much easier to hit and less likely for them to be countered. Also, this would put him in position for either Lewis or the Klitschko's to hit him with their best stuff since he's coming in. Byrd is at a huge strategic disadvantage if he has to go to a taller fighter who can hit.
See the Catch-22 Byrd would be in against a taller opponent with a good jab and who knew how to use it. If he backs off and tries to lure them in so he can counter, he ends up eating jabs all night and loses a decision. On the other hand, if he goes to them, he's walking right into their power zone. As much as I like Byrd, in a fight versus Lennox Lewis, I just don't see how he could win. Either Lewis or the Klitschko's could control him with their jabs, or they would stop him if he tried and pushed the fight.
So in a nutshell it breaks down like this. If you are not significantly taller than Byrd with a long reach and a good jab, or if you're not a swarming/pressure style fighter, how do you beat him? The answer is that his opponent should never go to his head with their lead punches, because they'll most likely miss and get countered. The best thing to do is to go to the body, and then come up to the head. The other thing to do is jab at his chest, this insures that you will hit something and break up his rhythm and keep him off balance. And it's imperative to cut off the ring against him. Lastly, to beat him his opponent can never wait on him, he must force Byrd to react. Like with Roy Jones, if you wait on him and try and react to what he does, it's too late!
Since Byrd is such a clever and cunning fighter, his opponents must have a plan when they fight him. He certainly does, and follows it to perfection. When fighting Byrd, the opponent must force Byrd to adjust and take away what he likes or is best at. In other words, make him react to what you are doing instead of reacting the way he plans for you to.