Josh Hedges/Zuffa LLC/Getty Images

Cain Velasquez seemed completely unstoppable not all that long ago. His wrestling was too good. His hands were too heavy. His gas tank was too deep.

He could outwrestle strikers, outstrike wrestlers and outlast anyone.

That made his reign as UFC heavyweight champion somewhat disappointing, given the fact that his 896 days were defined by two yearlong layoffs due to injuries. It made his fall from the throne almost tragic, as factors outside his control directly contributed to the loss. And it makes his fight at UFC 200 opposite Travis Browne one of the most important of his career.

The UFC heavyweight division is defined by its inconsistency. While champions like Jose Aldo, Georges St-Pierre and Anderson Silva anchored their respective weight classes for years, the heavyweight division has seen champions come and go quicker than anywhere else.

The longest title reign in UFC history before Velasquez? Brock Lesnar's 707 days. The most defenses? Just two, a record shared by Lesnar, Randy Couture and Tim Sylvia.

Josh Hedges/Zuffa LLC/Getty Images

Velasquez was supposed to be the one to change that, and, for a time, it seemed he was up to the task.

Video Play Button Videos you might like

After a short-lived run as champion, losing to Junior Dos Santos at UFC on Fox 1, he exacted his revenge and retook the belt with an uncomfortably lopsided beating of the Brazilian at UFC 155. Then, he was off to the races. His first defense, where he mauled Antonio Silva, started him off on the right track. His second victory over Dos Santos was even more thorough, and put his name alongside those of Lesnar, Sylvia and Couture as the only men to notch multiple title defenses in a single reign.

Alas, like most other sure things before him, Velasquez's demolition of the division did not come to pass.

After missing all of 2014 due to knee injuries, he eventually returned at UFC 188 and lost his title to Fabricio Werdum with what is widely regarded as one of the worst performances of his career.

Statistically speaking, the fight wasn't a wholly bad performance by Velasquez. He landed dozens of punches on a crafty, skilled veteran (88, according to FightMetric) and scored four takedowns over two-and-a-half rounds. Just as importantly, he wobbled Werdum on multiple occasions before succumbing to a guillotine choke during a takedown attempt.

Jeff Bottari/Zuffa LLC/Getty Images

All in all, Velasquez turned in a solid performance against Werdum. "Solid," however, was much less than fans were used to with Velasquez.

His wrestling lacked his signature pop and potency. His always-questionable striking defense finally proved to be a legitimate flaw. Worst of all, his inhuman cardio was seemingly gone.

It was the kind of performance that, naturally, goaded fans into a wave of hot takes about whether or not Velasquez was ever any good. Much more importantly, it drew questions from pundits about whether or not Velasquez's extensive injury history may have ended his career before it truly began.

Going down the list of Velasquez maladies, it certainly seems possible. The former champ has suffered a slew of injuries over the years, and it's astounding that he's still competing when looking over the list:

Those, of course, are just the ones that have been made public. It doesn't include the countless tweaks, pulls, fractures and tears that he has undoubtedly worked through in training. Any sports fan knows that a knee, back or shoulder injury can wreak havoc on an athlete's career, and Velasquez has needed surgery on all three.

However, it gets worse. While Velasquez was initially granted an immediate rematch against Werdum in February, he was forced to withdraw and was replaced with Stipe Miocic, who took the title from Werdum with a dramatic first-round knockout at UFC 198. Miocic has since been booked to face Alistair Overeem at UFC 203.

That, unfortunately, leaves Velasquez with no clear path to the title and in rebuilding mode both competitively and promotionally. That raises the stakes in a big way for Velasquez at UFC 200.

Mike Lawrie/Getty Images

Browne is a good fighter, but he has stayed an arm's length away from elite status for his entire career to this point and lacks especially potent skills in any given area of the game. He has pure knockout power and is considerably larger than the majority of UFC heavyweights, but isn't technically astounding and lacks raw athleticism. That makes him a perfect barometer for where Velasquez is at this point.

It's impossible to estimate how steep Velasquez's decline has been in recent years, given the simple fact that he has fought just once since 2013. What's more, there are several built-in explanations for Velasquez's poor performance at UFC 188 that are separate from his injuries, including a lack of preparation for a fight in Mexico City's high altitudes, general rustiness and getting wobbled early in the fight. Still, Velasquez has lost a step over the last few years, and that could prove to be the difference here.

Velasquez circa 2013 most likely takes the win over Browne without much difficulty, utilizing his wrestling early and plying his superior cardio late to either take a decision or a late finish. Velasquez circa 2016 against Browne, though, is anyone's guess.

This fight at UFC 200 is one of the rare instances where, truly, anything can happen, and it could set the trajectory for the remainder of Velasquez's days as an active competitor.

Velasquez could win in emphatic fashion and be in line for a title shot come the holidays. On the other hand, he could end up on the bad end of a lopsided beating and be relegated to smaller Fight Night events for the remainder of his UFC career.

The stakes are high across the board for everyone competing at UFC 200. For Velasquez, though? Everything is on the line.