Despite the fact that the sport of mixed martial arts (MMA) as we know it today is not yet 20-years-old, we've gone through a few eras. I won't bother to get into what they are, I just make mention of them because we're now in the era of the dominant champion.

Five of the seven major weight classes (let's not add flyweight just yet) in the UFC feature a champion with multiple title defense under their belt and no end in sight to their respective reign at the top of their divisions. One of them, featherweight king Jose Aldo, can't even find a challenger to his throne.

It's not for lack of trying on part of matchmakers.

UFC President Dana White has done his damnedest to find a suitable lightweight to shed some skin for an immediate title shot at 145-pounds. Just as soon as Frankie Edgar lost the lightweight championship to Ben Henderson, White was on the phone attempting to set up a fight against Aldo. "The Answer" resisted, though, and was eventually granted a rematch.

Then talk turned to Anthony Pettis, another top 155-pound contender with enough credibility to earn an immediate crack at "Scarface." But after initial flirtation with the idea, "Showtime" emphatically denied he was seriously considering it and vowed to win the belt he actually wants, which is the title currently sitting somewhere close to Henderson.

Other lightweights who made the drop (Ross Pearson, Dennis Siver) simply don't measure up.

It's difficult to understand why exactly elite lightweights are passing up a chance to square off against one of the pound-for-pound best fighters in the world. This is cagefighting, of course, so fear certainly isn't something to consider, or at least you wouldn't think. It's baffling, though, that multiple men have been told they could headline a UFC event and fight one of the best in the world for a title and have said no.

Aldo, meanwhile, languishes on the sidelines, lying in wait for someone, anyone, to step up to the plate.

The list of potentials is short -- let's go with five -- but let's see if we can't find one for him.

1. Anthony Pettis -- Okay, so he already said no and he's not dropping down. But someone needs to get in his ear and explain to him that he could headline an event against one of the best in the world with a title on the line that he could help bring prestige to. Is featherweight as deep as lightweight? Of course not, but considering he's a far more marketable champion, if he had the title, the promotion could get behind him and push him to the sky.
   
2. Dustin Poirier -- He first made waves when he destroyed Josh Grispi, who had previously been scheduled to fight Aldo. Since then, "The Diamond" has fine tuned and sharpened his skills to the point that a win over Chan Sung Jung this upcoming May 15 in Virginia will put him next in line. Can he win? Maybe. That's enough to give him a shot.
   
3. Hatsu Hioki -- He's on a six fight winning streak and is 2-0 inside the Octagon but hasn't exactly blown anyone away with his performances since making his way stateside. Still, he's solid when the fight hits the floor and could avoid Aldo where he's most deadly. He's a long shot to win but a viable challenge nonetheless.
   
4. Frankie Edgar -- His inclusion on this list is based on two things: 1) Featherweight seriously lacks depth and 2) Aldo really, really wants to fight him. It's too bad, really, that he feels like it would be a slight to the 155-pound weight class to move down because he would bring out the very best in "Scarface." At the end of the day, it's one of the best match-ups available that may never happen. It would also be one of the most competitive main event level matches ever. This fight needs to happen sometime or another, even if Edgar loses to Ben Henderson again when they hook back up.
   
5. Chan Sung Jung -- Believe it or not, he's the next best option. If he bests Poirier at UFC on FUEL TV 3, that will only give him four wins in his last seven fights but he will have ripped off three in a row, two in seriously impressive fashion. Remember the twister submission of Leonard Garcia? Or the seven second knockout of Mark Hominick? Destroy Poirier and he's headed for the big time, even if a rude awakening awaits him.
   

That's the lay of the land, folks. Sadly, we're rapidly approaching the point where we'll start bugging UFC Bantamweight Champion Dominick Cruz to move up in weight to challenge Aldo.

One thing is for certain, though: the sooner the Brazilian butt-kicker gets back inside the cage, the better.

Now, Maniacs, tell me who you want to see him fight next.