Once upon a time in the not-so-distant past, lightweight kingpin B.J. Penn was considered one of the top pound-for-pound fighters in the world right alongside middleweight Anderson Silva and welterweight Georges St-Pierre, Benson Henderson was the lesser-known WEC lightweight champion, and no one had ever heard of Chris Weidman, Jon Jones or Anthony Pettis. Since that time, Penn has gone on to lose his UFC lightweight belt as well as four of his last six matches, Silva was knocked out in devastating fashion in a massive upset, and GSP has announced that he is taking an indefinite leave of absence from the sport. Talk about a lot happening in four short years’ time.

When Frankie Edgar first defeated Penn, many thought it was a close decision. They had an immediate rematch which left even the most devout Penn fans unable to argue that Edgar was the champion. Despite besting someone many considered one of the greatest fighters of their generation not once but twice, Edgar still did not receive the respect he deserved as UFC lightweight champion of the world. This would also be the beginning of the division’s “rematch era.”

Edgar next faced the only man to defeat him up until that point in his career, Gray Maynard. This fight made sense not only for the marketability of a rematch, but also because Maynard was the fighter many felt Edgar cut in line for the title and who had a very believable chance of besting the champ. Unfortunately, their second bout ended in an extremely controversial draw and a third match would be necessary in order for Edgar to solidify his status. But the injury bug struck, causing the bout to not take place for 10 months and further holding up the division from allowing other contenders a crack at the title. And so the rematch era continued.

Edgar knocked out Maynard in the fourth round of their third bout, thus ending the controversy, at least for the time being. This would be the only time Edgar would finish an opponent, or have a fight finished at all, while fighting for a UFC title. By contrast, Penn, who while having over twice as many losses as Edgar, would only win one fight by decision in his entire UFC lightweight career, finishing all the other eight of his 155-pound opponents, including when he captured the vacant title and subsequent three title defenses prior to facing Edgar.

Finishing power is not necessary to build star power—just ask GSP. But it sure does help—just ask Johny Hendricks. Of course, when your contenders are so closely matched to your champions and you have close decisions occur on multiple occasions involving different people, it’s hard to build momentum behind those fighters to headline a pay-per-view card.

Former WEC lightweight champion Benson Henderson captured the title from Edgar in a controversial unanimous decision, again showcasing how competitive the weight class is. But the problem was that you had to give the former champ the chance to retake his belt, the same way Penn was afforded that opportunity. So the rematch era continued and it was met with an equal, if not greater, amount of controversy when the judges award a split decision victory to Henderson. No third match occurred, however, as the UFC wanted the division to move on. Edgar was persuaded to drop to 145 pounds because, despite winning and defending the UFC title, he was visibly outsized by his recent competition.

With two of the last four lightweight champions leaving the division, one would think that it would begin to open up to new talent in new exciting ways. Unfortunately, the exact opposite occurred, and with so much top-level talent, it’s hard to sort the pretenders from the contenders while trying to escape the rematch era.

Henderson successfully defended his title in a one-sided match against perennial trash-talker Nate Diaz in front of a hometown crowd in the main event of a Fox card. For that one second, it seemed the UFC had a true champion worthy of the title to dominate all comers and become a true superstar. Except that two other fighters had different plans. Longtime top-ranked Strikeforce champion Gilbert Melendez and the looming shadow of Henderson’s existence, Anthony Pettis, the last man to beat Henderson and capture the WEC lightweight title.

In another Fox card, Henderson won a split decision over Melendez just as controversial as his fights against Edgar, and although a rematch could be justifiable, it didn’t take long for the pundits to clamor for Henderson to face the “true champion,” Pettis, and solidify who should be at the top of the division. At last, the rematch era ended with one convincing win. Pettis submitted his way to the title in what would be Henderson’s only UFC bout to not result in a victory. At last, the division would have a champion who could win in convincing fashion against someone who had narrowly defeated two of the best the world had ever seen in Edgar and Melendez, and there would be no need for them to fight again any time in the foreseeable future, as Pettis had already bested Henderson once before. Therefore, the rematch era has come to an end.

Of course, at least with the rematch era, it was clear who would participate in the title fights. Under Pettis’ reign, it’s unclear when and who will partake in the next match, no thanks again to the injury bug. T.J. Grant was the next contender at one point, but an injury kept him out of two title fights. Josh Thomson was ready to step up to the plate, but the injury to Pettis saw Thomson’s chances for UFC gold disappear, at least for the moment. But now we might be entering a different, yet equally frustrating, time where the contenders may have to rematch, or continue to fight, in order to vie for the title. Thus is the problem when the best in the division fail to win convincingly at the top.

Despite sitting at No. 1 in the Official UFC rankings, Henderson will have a long and arduous journey if he wants to wear the belt again, at least so long as Pettis is atop the division. Of course, right at No. 2 is Melendez, who stands a good chance of fighting for the title with one more win, but the argument is hard to make with the loss to Henderson still fresh in recent memory, and a rematch would help him cut in line. But that’s assuming the UFC even wants to do a rematch, for fear it would have another controversial ending, as both fighters are prone do to, and leave the promotion without a clear contender.

Melendez isn’t the only fighter who might need a rematch in order to get fast-tracked to a title shot. Thomson will still fight as scheduled, but instead of a shot for the belt, his fight will be against Henderson. A win will help ensure he maintains his status to fight for a title, and it will likely move him from No. 4 to at least No. 3, where Grant currently sits. But if it does not, then that will only leave one person in his way: Melendez. Considering they have already fought three times, with Thomson coming up short on two, that’s another hard sell for the UFC, especially if it means risking another split decision, as was the case in their last bout.

Rounding out the top five is Diaz, who avenged his loss to Maynard after losing his last two bouts to Henderson and Thomson. So, it’s no surprise that he may need to fight at least one person who already convincingly defeated him if he truly wants another title shot. Then again, although he’s at No. 5 and may need a rematch like Thomson and Melendez to continue his climb, he has yet to face the current champion once, like Thomson and Melendez have, and it is very possible this is the direction the UFC would prefer to go. Not necessarily to have Diaz skip the line, but to avoid reentering another rematch era.

It’s unfortunate the division is one that sees less success than it’s heavier siblings, but it also shouldn’t be surprising, since it has been several years since it had a dominant champion void of controversy. However, it’s not because of a lack of talent. It’s because the talent is so rich and deep, and thus the matches become extremely close. This is ultimately a good thing, because it will ensure that if and when such a champion emerges, they will once again reenter talk of being one of the top three, if not very best, pound-for-pound fighters.

Pettis may in fact be that champion, and hopefully he can have a healthy and speedy recovery and continue to put on the same highlight-reel performances fans have come to appreciate, but until then we may end up seeing the division’s top talent continue to jockey for position, and it may end up containing a few rematches. Fortunately, those rematches will not be for the title and will only help ensure the truly best are fighting for the title, as well as maybe put new blood in the mix. Then again, legacies are often built on rivalries, and no division is filled with more close matches and bitter upsets than the lightweights. And that’s the bottom line.