The Hall of Fame enshrinement ceremony is coming and it's providing a platform to honor some of the most influential figures in basketball history. Players like Allen Iverson, Sheryl Swoopes and Yao Ming have made an indelible mark that goes past basketball thanks to their contributions to the cultural zeitgeist. Yet when it comes to actual impact on the game itself, one name stands out.

Shaquille O'Neal is, without a doubt, the headliner of this amazing class. Through sheer power, he became one of the best players in league history. His size and athletic ability also made him a part of a rare breed of overwhelming big men that disappeared when he retired.

NBA history is littered with big men that dominated in unprecedented ways. But that lineage, which started with George Mikan, seems to have ended with Shaq. Here are the many reasons why there may never be another player like him.

Shaq really was a freak of nature

This should go without saying, but the NBA has rarely seen a physical specimen like O'Neal. The Orlando version was capable of doing things no 7'1 behemoth should have been able to do. His explosiveness and quickness were off the chart.

"You know what he looks like?" Hakeem Olajuwon told The Blatimore Sun during his rookie year. "A bigger me."

Even after gaining weight and losing some of his nimbleness late in the year, Shaq’s power was unmatched. He could push anyone under the basket, and once he got the ball close to the hoop, it was game over. He was too strong, too skilled and too athletic.

"He makes 6’11, 270-pounders look like they're not even there," said then Nets President of Basketball Operations Rod Thorn about O'Neal in 2001 to USA Today. "I don't know if we've ever had a player with the combination of quickness, strength and size as Shaq. (Bill) Russell was finesse; (Kareem Abdul-)Jabbar was elegant, very talented but not physical. Shaq whips you down, then dunks you through the basket.

"For the time (Chamberlain) played, Wilt was bigger, stronger and quicker than every player who was near his size. Shaq is bigger, stronger and quicker than Wilt."

LeBron James is the closest the modern NBA has come to seeing someone with unprecedented power and quickness for their size, but he’s a wing player. Shaq was something else.

The league changed rules to prevent future Shaqs from dominating

Few players are so powerful that they inspire rule changes, but Shaq was one of them. Before the 2001-02 season, the league eliminated its byzantine illegal defense rules. That paved the way for zone defenses, with the only restriction being that no player could stay in the paint for more than three seconds unless he was guarding someone closely. It's no coincidence the tweak came during Shaq's prime.

O'Neal predictably didn't like it.

"The NBA is for men, and a grown man doesn't need to play zone," he told SI.com in 2001. "Why do you think they call it man-to-man? If you can't play it, you shouldn't be here."

It's hard to blame him for criticizing the rule changes. Prior to them, it was simply impossible for defenders to contain Shaq one-on-one. Soft doubles and roaming resulted in illegal defense calls, while double-teaming him created wide open shots for his teammates.

But once it became legal for teams to play zone, the choice wasn’t as stark. Defenders could stand in the paint for three seconds without guarding anyone and threaten to double team without actually having to commit to it. This made the lane O’Neal once owned more crowded. These days, post players like O’Neal not only have to beat their own man, but also one or two others that lurk in help positions on the opposite side.

Shaq still had a couple of excellent seasons after the change, but even someone as powerful as him was somewhat limited by the more sophisticated defensive schemes that emerged thanks to those rule changes.

Centers don't want to play like Shaq anymore

In a recent interview with The Vertical's Shams Charania, Shaq posed a theory about the death of the back-to-the-basket big man:

"I believe the way that I dominated, I made guys not want to come inside and feel the pain. That’s why you have a lot of guys stepping out and shooting jumpers now. We’re all products of our environment, so when I was coming up, I saw big men playing in the middle. The kids saw me playing and realized that they couldn’t endure the pain and nor did they want to take the pain. So they started shooting jumpers – a la Dirk Nowitzki."

O’Neal may be crediting himself too much for such a major shift in attitude, but it’s hard to deny that young big men dream to play on the perimeter more these days. This is due to a combination of factors, including a fear of banging inside, the rule changes marginalizing post play, the advent of analytics that point to more efficient ways to score and more. Regardless, O'Neal is right that most big men today don't try to overpower defenders in the post like he did.

Dwight Howard punished teams inside for a few seasons in Orlando, but he was never as effective as Shaq, much to Shaq’s delight. Two of the three All-NBA centers from last season -- DeAndre Jordan and Andre Drummond — are big and athletic, but thrive in the pick-and-roll rather than the post. DeMarcus Cousins has the strength and post moves to do a decent Shaq impression, but even he drifts to the perimeter too often.

Barring another round of rule changes, the days of watching big men bully their way to the rim seem over.

Huge centers are exposed on defense

The league has changed greatly since Shaq's days. The three-pointer is a bigger part of every offense now and almost every team has at least one big man who can shoot from beyond the arc. Dribble penetration has replaced post play as the primary mechanism to get the ball to the paint.

As a result, the defensive responsibilities of big men have changed. Those built like Shaq tend to struggle with their new duties.

Centers now have to step outside to the perimeter on pick and rolls or risk allowing open three-pointers to the ball handler. Rim protection matters, but the ability to switch — or at least step out on the floor to corral perimeter players — has become more important. Even at his athletic peak in Orlando, Shaq was more comfortable standing in the paint. Today, he wouldn't be able to stay there.

Someone with O'Neal's strengths would be an offensive force in today's league. Yet he’d also be exposed defensively, which negates some of his impact on the other end. How can those players be franchise cornerstones if they are so limited on one end of the floor?

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Watching O'Neal play was exhilarating because he really was one of a kind. There were amazing big men in the era he played, but no one came close to matching his physical dominance. He was so naturally gifted that he made things look easy, which infuriated critics who failed to recognize the finesse behind the power and thought he just skated by on his gifts alone.

The center position will still matter in the future thanks to young stars like Karl-Anthony Towns and Anthony Davis, but the way O'Neal dominated won't ever be replicated. Shaq was the last of a breed that no longer exists, and likely won’t be revived anytime soon.