The Cube in the Cage.

These heavyweights are not to be taken lightly.

Buoyed by the mainstream exposure that the UFC has received while being prominently featured on Spike TV for the last two years, the sport of mixed martial arts is in a boom period. Fighters like Chuck Liddell, Tito Ortiz, Randy Couture, Matt Hughes, Georges St. Pierre and Rich Franklin have become household names, while attendance and pay-per-view numbers have skyrocketed. As big as MMA – and the UFC in particular – has become, however, it is clearly the bigger fighters that have been carrying the least weight.

In the UFC, which is arguably considered the premiere MMA organization, there is Tim Sylvia, Andrei Arlovski, Brandon Vera, and then everybody else. Fighters like Paul Buentello, Justin Eilers and, most recently, Jeff Monson – all talented in their own right –have received title shots without defeating a legitimate top contender, while other less-deserving heavyweights have been given opportunities to fight in the UFC without boasting even a single noteworthy victory.

Enter MMAagents, and its stocked roster of heavyweights. In addition to undefeated heavyweight prospect “Irish” Jake O’Brien (who is now 9-0 as a pro, and 2-0 in the UFC after defeating Josh Shockman at UFC 65 a few weeks back), there is Justin “Insane One” McCully, Wes “The Project” Sims, Mark Kerr and Vince Lucero. And there is one other guy on the MMAagents list that you may have heard of – former UFC heavyweight champion Ricco Rodriguez. But if you think this is a case of Ricco and the other guys, you are wrong.

Take McCully, for example. The longtime workout partner of Ortiz (the two are currently training together, along with O’Brien, up in the high altitude of Big Bear, California for Tito’s fight against Liddell on Dec. 30), McCully recently returned from a three-year hiatus away from MMA by winning two fights over a three-week span. One of those was a quick first-round submission victory in October over Warpath, who just this past weekend at Strikeforce took Buentello into the second round before losing to the “Headhunter.”

McCully, who started his fighting career in 1997, has returned in great shape and dominated both of his recent opponents on the feet and on the ground, but yet, the 6-foot-2, 235-pound Team Punishment standout still waits for that call to make his UFC debut. “The Insane One” is due, and he deserves his shot.

Then there’s Sims, who is followed by controversy like Butterbean follows a Big Mac. There was the infamous stomping of Frank Mir, as well as the biting incident with Mike Kyle. Though the cynics are quick to point out Sims’ 0-3 record in the UFC, the fact remains that all of his fights in the octagon were entertaining and competitive. What’s more, Big Wes has gone 9-1-1 in his last 11 fights, including a controversial-as-usual first-round TKO over Kimo at X-1 in October.

Sure, Sims is loonier than Bugs, but his recent record speaks for itself. If Kevin Jordan and Sherman Pendergarst deserve UFC shots, surely Sims has earned another chance.

As for Kerr and Lucero – one, a legend in the sport, the other a proud journeyman brawler who has displayed moments of greatness – their respective path to the big show certainly has some hurdles to overcome. Kerr is a two-time UFC tournament winner (UFC 14 and 15), who then went on to become an even bigger star in Japan with the Pride Fighting Championships. The documentary “The Smashing Machine,” was shown repeatedly on HBO and turned Kerr into a fallen star of sorts, as it made aware his struggle to overcome an addiction to painkillers. But Kerr has returned healthy, despite losing his recent comeback fight against Mike Whitehead in an IFL Superfight. Up next for Kerr is the England-based show Cage Rage, where he looks to win his first fight since 2000. If Kerr can once again become the Kerr of old, there isn’t anyone in the sport he doesn’t match up well against.

Lucero, on the other hand, has never made it to the big time, despite his 17-10 professional record. Those 17 victories include wins over TUF 3 finalist Josh Haynes and Jonathan Ivey, but he’s been most impressive in losses to Eilers and Eric Pele. The decision loss to Pele in October showed that a fight with Lucero is no cakewalk. Just this past weekend Pele knocked out then-undefeated Antonio Silva, giving even more credence to just how tough Lucero is. Looking at the list of IFL heavyweights, there is no question that Lucero would fit in nicely there.

And then there’s that Ricco guy. The former UFC titleholder, Rodriguez (25-6 record) holds wins over Couture, Arlovski, Monson, Buentello and countless others. Most recently, Rodriguez decimated Ron Waterman at the WFA in July, winning by TKO when the referee stopped the fight after the first round. As gifted a fighter as there is in the heavyweight division, Rodriguez is now looking for the opportunity to fight the guy who took his belt in the first place – Tim Sylvia. Having lost over 80 pounds in the last year, Ricco has re-dedicated himself to becoming champion. If anybody deserves a chance, it is Ricco Rodriguez.

So yes, the heavyweight division is the weakest division in the UFC. And yes, the heavyweight division is in dire need of a boost. So look no further, because we have some of the best of the big boys right here. From top to bottom, these heavyweights are not to be taken lightly.