While Cormier has said he'll be dropping to 205 pounds regardless of the outcome over the weekend, Nelson recently posted a picture to his Facebook page of him looking much trimmer than usual. Due to the magnitude of their matchup at UFC 166, the winner could be an immediate title contender in the light heavyweight division.
Of all the heavyweights on the UFC roster, only Mark Hunt is shorter than both Cormier and Nelson. At 5'11" Pat Barry stands at an equal height with Cormier. With Cormier and Nelson both having a little extra girth around the midsection, it's unsurprising that they'd be considering a move to a lower weight class.
Which heavyweight will set up a potential light heavyweight title run on Saturday?
Here is a closer look at how Cormier and Nelson match up against one another in all areas.
American Kickboxing Academy has turned many wrestlers into top-notch strikers, and Daniel Cormier is not looking like an exception.
While it wasn't his most dazzling striking display, Cormier's work against Frank Mir along the fence was impressive on some level. The former Olympic wrestler did a solid job of mixing his world-class clinch grappling with dirty boxing to wear Mir down over three rounds.
Facing another jiu-jitsu practitioner in Roy Nelson, Cormier may look to utilize a similar game plan at UFC 166. Working along the cage against Nelson would allow Cormier to make use of his wrestling ability without putting himself in danger of submissions or being at range for his opponent's power punches.
Nelson has a tendency to cover up when cornered, which will aid Cormier should he find a way to get "Big Country" moving backward.
In the opening round of his most recent outing against Stipe Miocic, Nelson was pressured and turned into a punching bag in moments when he had no room to retreat.
After forcing Nelson into the fence with a left hook (top left), Miocic drove his knee into his opponent's arms (top right), creating an opening for a left hook to the body (bottom left). With Nelson staying stationary, Miocic was also able to end his combination with a damaging right elbow (bottom right).
The work from Miocic here is very reminiscent of Cormier's against Mir.
While simultaneously minimizing risk, Cormier can take away Nelson's wind with body shots from the clinch. Cormier probably has the speed to beat Nelson from a distance as well, but there's no reason to give "Big Country" a chance to unleash looping right hands when he can win another matchup on the inside.
There's not a lot of problem solving to do in preparation for Roy Nelson's striking.
All his opponents know to look for the overhand right and right uppercut, but "Big Country" still finds a way to land with his power hand regularly. As surprising as it is for a fighter of his stature, footwork is one of the main reason's for Nelson's success.
Like Daniel Cormier, Nelson does a good job of controlling the center of the Octagon, especially early in fights. It will be interesting to see which fighter has more success moving forward on Saturday, as that alone could determine how the fight goes when standing early on.
Against Cheick Kongo, Nelson was able to corner his opponent and prevent him from circling away from his right hand (top left). When Kongo tried to circle to Nelson's right and land a leg kick (top right), "Big Country" stepped in and met the Frenchman with a huge overhand right (bottom).
Where Kongo didn't want to circle into Nelson and clinch initially, Cormier would have the confidence to work off of the fence from the clinch rather than risk circling into a right hand.
More concerning to Cormier than his footwork on the edge of the Octagon is Nelson's footwork and countering in the center. It negated a speed disadvantage against Matt Mitrione and could do the same against Cormier on Saturday.
Above, Mitrione loaded up a straight left as Nelson stepped forward with his lead leg (top left). Nelson quickly pivoted, moving his head out of the path of Mitrione's punch, and countered with a big right uppercut (top right). Already rocked by the right hand that him him from a blind angle, Mitrione also ate a left hook and overhand right on his way down to the canvas (bottom).
Nelson may not have the quickness or volume striking to beat Cormier in a striking match over three rounds. However, in space, he still has the power to end this fight with a single punch.
Fighters don't just toss Josh Barnett around like Daniel Cormier did during the Strikeforce Heavyweight Grand Prix finals. A former Olympic wrestler, Cormier's wrestling is simply on another level than most UFC heavyweights.
Having defended 60 percent of takedowns he's faced inside the Octagon, Nelson is a pretty solid defensive wrestler. However, he was taken down six times over three rounds in a bout with Frank Mir, and Cormier pretty much had his way with Mir in the clinch at UFC on Fox 7.
Cormier didn't score any takedowns against Mir, but he also hardly looked for any, wary of the former champion's submission abilities. Nelson is also skilled on the ground, but he's not nearly as dangerous off of his back as Mir was.
He could easily implement the same exact game plan he used against Mir when he faces Nelson, but Cormier may look to work from the top this time around. Nelson won't have many answers if he does.
Daniel Cormier has not been taken down in his UFC career.
Considering he's already shut down attempts from Josh Barnett and Antonio Silva, Cormier isn't likely to give up his first takedown to Roy Nelson. In 10 UFC fights, Nelson has only taken down a fading Mirko Filipovic and Brendan Schaub.
As strong as he is on the ground, Nelson isn't great at getting there with his own takedowns.
Nelson attempted one takedown in his most recent bout with Stipe Miocic, and it was of the sloppy variety.
Against Miocic, "Big Country" dove in on a double-leg attempt in the first round (top left). Instead of cutting the corner and using his head to push Miocic off balance, Nelson drove forward without keeping his feet under him (top right). Miocic turned and allowed Nelson's momentum to carry him to the ground. As Nelson tried to compensate and turn into him, Miocic circled in the opposite direction, blocking Nelson's right arm from grabbing his legs in the process (bottom left). Miocic took Nelson's back and landed a right hand (bottom right), turning a poor Nelson takedown attempt into an advantageous position.
If Miocic can make his takedown attempts look this ugly, Nelson may not even want to try shooting in on Cormier.
Daniel Cormier finished multiple Strikeforce opponents with his ground-and-pound, but it's tough to see him finishing Roy Nelson on the canvas.
Aside from submissions due to punches, which isn't going to happen against the iron-chinned Nelson, Cormier's only other submission win came in King of the Cage over three years ago. Surely Cormier's jiu-jitsu is improving daily, but it'd be shocking for him to become the first fighter to submit Nelson. This is considering "Big Country" has gone to the ground with Frank Mir and Fabricio Werdum over the past few years without having to tap.
Nelson doesn't often find himself on his back, but when he does, he favors working toward escapes rather than reversals. "Big Country" has also not been known to threaten with submissions when on bottom.
If he decides to go to the ground with Nelson, Cormier should be able to do some damage and score points with ground-and-pound, while Nelson works himself back to a standing position.
Taking Daniel Cormier out of his comfort zone with a takedown might be a good idea for Roy Nelson in theory, but that doesn't make it any more of a realistic possibility.
As previously mentioned, Cormier's never been taken down, and Nelson has certainly not taken down anyone with similar wrestling ability. Moreover, Nelson has not been credited with a reversal in his UFC career, making it seem unlikely he'll end up on top at any point on Saturday.
If he did, it's difficult to say how Nelson would fare on top of Cormier, as it's not a situation we've seen Cormier in.
One would think he's developed enough of a ground game to survive underneath Nelson, who hasn't secured a submission in over seven years. It's near impossible to say, though.
Daniel Cormier has already fought some of the best in the world only 12 fights into his MMA career. However, "DC" still lacks experience in comparison to Roy Nelson, who has competed in more than double the fights Cormier has.
At the same time, that also means Cormier has endured less wear-and-tear than Nelson. Though both are in their mid-30s, Cormier appears to have better conditioning and looks to be much lighter on his feet than Nelson.
Neither fighter has a significant reach advantage, and both heavyweights have remained relatively active lately.
Overall, intangibles shouldn't play a huge factor in this matchup, with the possible exception of Cormier emptying Nelson's gas tank with punches to the body.
Much like his teammate, Cain Velasquez, in the UFC 166 main event, Daniel Cormier's biggest worry on Saturday will be the one-punch knockout power of his opponent.
Cormier is the better wrestler in pretty much any matchup he could be given, and that's no different against Roy Nelson. With the ability to beat Nelson in the clinch and on the ground, Cormier shouldn't have to see much of Nelson's haymakers, but he may even be at an advantage when striking from range where they will be coming at him.
Expect Cormier to approach this fight much like he approached his fight with Frank Mir. A takedown or three may be mixed in this time around, but dirty boxing against the cage should be a feature in Cormier's game plan.
As long as he keeps that left hand tight to his chin when closing distance, Cormier should emerge from UFC 166 still undefeated.
Cormier defeats Nelson by decision.
Photos via UFC.com. Statistics via FightMetric.com.