Cain Velasquez has finished eight foes inside one round. | Photo: Dave Mandel/Sherdog.com

UFC Heavyweight Championship

Photo: D. Mandel/Sherdog.com

“Cigano” wields one-punch KO power.

They say good things come in threes, and never has that been truer than in the Ultimate Fighting Championship ’s heavyweight title scene.While the division has come a long way in improving its depth and talent in recent years, Cain Velasquez and Junior dos Santos continue to stand out among their peers, which is why the two big men will square off for a third time in the UFC 166 headliner. The first two meetings were a study in contrasts: Velasquez’s relentless pressure and wrestling earned him a dominant decision at UFC 155, while dos Santos’ dangerous knockout power carried him in their initial showdown at UFC on Fox 1.Could these two be in for a best-of-five series? Much hinges on how their trilogy plays out at the Toyota Center on Saturday in Houston. Here is a closer look at the UFC 166 card, with analysis and picks: Cain Velasquez (12-1, 10-1 UFC) vs. Junior dos Santos (16-2, 10-1 UFC)If the trilogy between Velasquez and dos Santos seems rushed, it is because it probably is. After this latest rematch, the two heavyweights will have squared off three times in little more than a two-year span. Dos Santos has beaten two men -- Frank Mir and Mark Hunt -- between meetings with the reigning champion. Velasquez, meanwhile, has knocked off Antonio Silva twice. While the third bout between the two certainly could have used some more buildup, there was also the chance that an upset loss by either fighter could have derailed the showdown altogether. At this point, Velasquez and dos Santos remain the class of the sport’s big men.However, the gap between the two might very well be larger than first believed. When dos Santos cracked Velasquez with an overhand right behind the ear to essentially end their UFC on Fox 1 encounter, it was a testament to the numbing knockout power of the Brazilian. To date, “Cigano” has finished 12 of his 16 professional victories by knockout or technical knockout. Still, it was jarring to see someone at Velasquez’s level go down so quickly.Velasquez was coming off a year-long layoff due to shoulder surgery and appeared far more tentative than usual during the abbreviated bout. Later, rumors surfaced that the American Kickboxing Academy product was also hindered by a knee injury leading up to the fight.While it can be easy to dismiss such talk as an excuse, it became clear one round into his rematch with dos Santos at UFC 155 that Velasquez was a completely different fighter than the one who appeared on Fox in November 2011. The Mexican-American heavyweight began moving forward immediately, throwing punching combinations and hunting for single-leg takedowns. Although dos Santos was able to successfully defend many of his opponent’s early advances, the constant pressure took its toll before the round had expired. As dos Santos’ pace began to slow, Velasquez capitalized by dropping him with an overhand right. The tone had been set, and many watching had to agree with the sentiments expressed by UFC commentator Joe Rogan at the end of the frame: “This is the real Cain Velasquez.”The title fight took on a rinse-and-repeat feel from there. Velasquez threw combinations, shot for takedowns and generally kept dos Santos on his heels. Even when the Brazilian was able to land a blow of his own, fatigue had robbed his punches of much of their sting. The statistics produced that night remain mind-boggling. Velasquez landed a whopping 111 significant strikes while also successfully executing 11 takedowns in 33 attempts. Thanks to sheer persistence and a seemingly bottomless gas tank, Velasquez put a beatdown on dos Santos the likes of which we had never seen. The overall offensive output generated by Velasquez that night would likely exhaust any other heavyweight who attempted to duplicate its execution.Barring injury, dos Santos faces a monumental task in Houston. To say he needs to improve his takedown defense would be inaccurate. Dos Santos has good hips and balance, and prior to UFC 155, he had only between taken down twice in the Octagon. The fact that he thwarted 22 Velasquez tries is remarkable in itself. Too often, however, the Team Nogueira product was caught moving straight backward rather than using angles or circling. Usually, that worked well, as he has been able to use his in-and-out movement to his advantage. Against Velasquez, however, he was rarely able to fully commit to his punches, and his generally outstanding work to the body was kept to a minimum. Dos Santos will have to take better advantage of countering opportunities, whether it comes from a telegraphed shot or a lunging Velasquez strike. Granted, those are few and far between, but they do tend to surface on occasion.Velasquez’s ability to get the single-leg and either score the takedown or force dos Santos to fight in close quarters with his back against the cage was a big part of his success. As well as Velasquez executed his game plan last time, it would be careless not to acknowledge the fact that it only takes one well-timed blow to turn the tide of a fight, and dos Santos is as equipped as anybody to make that happen. Better use of his jab this time around could serve him well to set up more damaging strikes.A short fight likely means dos Santos has found an opening to counter or hurt Velasquez with a combination. A longer time in the Octagon forecasts a fatigued challenger, with Velasquez imposing his will much the way he did at UFC 155. Velasquez is far from a one-dimensional wrestler, making it difficult to pick against him based on his previous effort against dos Santos. The champion retains his title by late TKO or decision.