Undefeated UFC lightweight champion Khabib Nurmagomedov will defend his belt against Justin Gaethje, the division's interim titleholder, on October 24—and it could be the last time we see him in the Octagon.

UFC President Dana White made this mammoth lightweight title fight official in an interview with CNN on Tuesday.

"It's going to happen, I'll tell you right here, right now," the UFC boss said. "That fight's going to happen: Khabib vs. Gaethje, October 24."

This news follows a turbulent few months for Nurmagomedov, who is 28-0 as a pro. The champion was originally expected to defend his title against longtime rival Tony Ferguson in April. Unfortunately, he ended up getting stranded in his native Dagestan, Russia, due to travel restrictions associated with the coronavirus pandemic, making that April encounter with Ferguson impossible.

With Nurmagomedov temporarily out of the picture, the UFC then matched Ferguson up with Gaethje in May, with an interim title on the line. Gaethje went on to win that fight via fifth-round TKO, derailing Ferguson's 12-fight unbeaten streak, and asserting himself as the next man in line for Nurmagomedov.

For a time, it looked as though Nurmagomedov and Gaethje would fight at UFC 253 in September. However, the death of Abdulmanap Nurmagomedov, the undefeated Russian's father, mentor and coach, shrouded the status of the bout in uncertainty. Nurmagomedov's longtime friend and training partner Daniel Cormier even told ESPN that he doubted the champ would fight again this year.

Given the events of the last few months, fight fans are understandably excited that Nurmagomedov, easily the most dominant fighter in the sport at present, will in fact be back in action before the year is out. However, the champion's legions of supporters should brace themselves for the possibility that this will be his swan song. 

Nurmagomedov has never made secret of the fact that he intends to retire young, and in 2020, when he's on the verge of clear-cutting his division, that retirement seems closer than ever. It's possible he will still strive to make good on his late father's wish and achieve a 30-0 record, but if he beats Gaethje—that is, of course, a big if—there will simply be no viable options left for him.

Think about it.

He'll have crossed Gaethje's name off his to-do list, just like he did Dustin Poirier's in September 2019.

Tony Ferguson, who long stood out as the most compelling challenge available for the champion, is riding a loss to Gaethje and will need at least another win before being back in title contention. Furthermore, most of the appeal of a Nurmagomedov vs. Ferguson fight stemmed from the fact that both men seemed unbeatable. After Gaethje pummeled Ferguson into applesauce in May, that's no longer the case.

Conor McGregor has been ravenous for a rematch with Nurmagomedov since he was submitted by the champion in October 2018. Yet the Russian and his team have been adamant that they will not give the trash-talking Irishman that opportunity any time soon.

"The only chance this fight could happen is in the street," Nurmagomedov's manager Ali Abdelaziz told ESPN in February. "[McGregor would] have to do something spectacular. He's s--t, you understand? 

"Conor McGregor is one of the biggest stars because he's one of the biggest scumbags." 

Nurmagomedov, of course, has long drooled over the idea of a superfight with former UFC welterweight and middleweight champion Georges St-Pierre, one of the few fighters with a run of sustained dominance to rival his own.

Previously, White has opposed the idea of a Nurmagomedov vs. St-Pierre fight, but he recently changed his tune, conceding that he'd allow Nurmagomedov to fight the Canadian legend in his retirement bout.  

"I would do anything Khabib wanted to do," White told ESPN when discussing the possibility of Nurmagomedov ending his career with a St-Pierre fight. 

While that comment from White understandably got fight fans very excited, it ignored one key detail: St-Pierre is retired.

The Canadian legend, who turned 39 in May, made his retirement official in February 2019 and exited the United States Anti-Doping Agency (USADA) testing pool thereafter, meaning he's not even eligible to fight in the UFC at present. 

As if all of that wasn't proof enough that he's done, he recently shrugged off the idea of a return against UFC welterweight champion Kamaru Usman. 

"I think for me it's better if I stay retired and I have other big projects right now," he told TMZ earlier this month. "I've done it for a very long time and unfortunately, in my sport, there's too many guys that retired too late and I do not want to be one of these guys. I'm very fortunate. I'm healthy, most importantly, and I'm also wealthy. I came at the right time, the right timing, I made a lot of money, and I think when I measured and calculated the pros and cons, it's better that I stay retired." 

St-Pierre is not fighting again.

So, as pleasant as it is to daydream to the contrary, Gaethje really seems to be the last viable challenger for Nurmagomedov. When you consider the death of the champion's father, which will undoubtedly change the complexion of his entire MMA career going forward, it seems increasingly likely that he will call it quits if he dispatches of Gaethje.

And if he does, he's earned it.