There have been a handful of perfect duos throughout wrestling history. These men are able to pull out the best in each other and tell stories in the ring that set an almost impossible standard. Shawn Michaels and The Undertaker are one of those rare pairings. Now, with The Undertaker set to say his "Final Farewell" this Sunday at Survivor Series -- the same event at which Taker made his WWE debut 30 years ago -- Michaels is hoping that "The Deadman" has found his peace in walking away from the ring.

In an extended conversation with CBS Sports, Michaels said that he was not familiar with The Undertaker (real name Mark Calaway) prior to his on-screen debut at the 1990 Survivor Series beyond having seen a few clips of him as Mean Mark Callous in WCW.

In the locker room, however, there was a belief that the character concept of The Undertaker would have a short life despite being unique.

"I was a lower midcard tag team guy at the time," Michaels said. "From the locker room scuttlebutt I was hearing, it was this unbelievably cool character. As I've told over the years, the biggest takeaway I can recall is everyone thinking it was very cool and a great idea, but we all questioned what kind of longevity a character like that can have.

"He's dead. He doesn't sell. It sounded from the locker room standpoint like maybe a limited character. It seemed like he would be very cool, but it would be short lived. Which, of course, 30 years later, that's pretty dang amusing if you ask me. But it speaks to Mark's ability. And then seeing it, it was a hard character not to think, 'What a cool idea.'

"That's pretty dang simplistic, but trying to recall a time ever seeing anything like that at that time or since -- I know it certainly has spawned a lot of maybe offshoots, so to speak. I don't know, I think it goes down as one of the greatest thought-up characters of all-time. I don't know how you could argue against that. And again, for him to have it last 30 years and still be unbelievably strong and awe-inspiring when he comes out, that's pretty dang impressive, and it's really tough to do."

Michaels credits Undertaker's longevity with attention to the smallest details. That allowed him to evolve from a literal zombie to a "living, breathing, feeling human being who was then just cast in the Undertaker." A large part of that transition came in the early 2000s when Calaway transitioned Undertaker away from "The Deadman" to "The American Bad Ass." Suddenly, he was riding a motorcycle to the ring and embracing a more "reality-based" approach to his character.

"To transition in and out of that, and obviously getting time off between that helped a great deal, but what makes both of them work is that none of them were ever too far separated from the human being," Michaels said. "A lot of that mirrored who he was and what he was going through in his life. ... When we're younger, we're all a little less [emotional], so to speak. The years passed and he got older and now he's a dad, he's a husband, he's gained a truckload of wisdom being in the wrestling business for 25, 30 years with injuries and ups and downs, happiness and sorrow. You experience a lot of things and all of that and all of those emotions and that journey was lived through The Undertaker as he evolved and turned him into this person."

Michaels stood across from Taker in arguably the three best matches of Taker's career. In 1997, the pair faced off at In Your House 18: Badd Blood in the first-ever Hell in a Cell match. In both 2009 and 2010, Michaels and Calaway put on two of the greatest WrestleMania matches ever at the 25th and 26th edition of the event.

They had been matched up opposite one another -- and occasionally on the same side -- many times throughout their lengthy careers, starting with their first featured singles match at In Your House 17: Ground Zero one month prior to the now-iconic Hell in a Cell bout. Michaels maintains that the WrestleMania 25 match between the two is not only the best of their pairing, but one of the most perfect things he has ever done.

"The perfect one is always going to be 25 to me," Michaels said. "But the first time in Louisville [In Your House 17 was special] getting in there with a guy you've never really been in there with and you recognize the uncanny chemistry you have with someone.

"Look, Mark and I were never friends. We weren't close, and we didn't ride together. Usually you have that chemistry with guys who you did do that with where you have at least a little more positive working relationship. Mark and I had just fantastic chemistry without ever really even talking to each other, which is pretty different. My two favorite matches I'll always enjoy will be the Hell in a Cell and fast forward what feels like 100 years later. To me, that's probably one of the most perfect things I've ever seen or done, and I think there are a lot of people who feel the same way."

Michaels is one of the few men in the wrestling business who seem completely content with their decision to retire. He hung up his boots for good after his WrestleMania 26 match with Calaway -- a bout that was billed as career (Michaels) vs. streak (Undertaker's 17-0 mark -- at the time -- at WrestleMania).

The Undertaker prepares to chokeslam Shawn Michaels at WrestleMania XXVI. WWE

Aside from a single tag team match in 2018, Michaels has not returned to the ring since that 2010 loss to Calaway. That ability to stay away from the ring, Michaels said, can be attributed to having the exact right match with the right performance and right opponent.

"At the time, I don't know that I had the ability to appreciate what I had and to recognize that moment," he explained. "Beforehand, I saw it in other people, but I didn't know what it was they were chasing. It's one of those things where you're thinking that they can't let go of this and the sound of the crowd or the money of the feeling special or feeling like they're a big deal. ... If you want to be happy and content and want peace in your life, you need to be able to let it go and step away knowing that's what it is instead of trying to take it up a notch or feeling it again or trying to go over."

"Look, if I could accurately describe it to people, I would certainly tell them because I see now and appreciate that it's such a challenge and a struggle for everybody else and I don't know that I had the ability to appreciate that I did it. All I know is that, coming home after that match, I did. My wife was driving us back to San Antonio, and I looked over at her and said, 'You know, I think that might have been the one. If I never did it again, I'd be happy ending on that one.' Of course, she didn't understand and was stunned by it. It wasn't too long after that that I made the decision to be the next one to walk away. Like I said, I wish to God I could tell you, but it was just a feeling.

"I think so much of it had to do with that it was Mark. It's a weird thing that we were always very different, but he and I had been there -- I got there in 1988, he'd been there since 1989 or 1990. We'd been through ups and downs and life changes. Believe it or not, it looks like two very different paths because we took them differently, but they're still very similar in a lot of ways and he knows and understands that. For us to be on separate sides of the locker room for all those years, but every time we stepped in the ring it was just magic. Then, to be at the end, and you go out there with him and now you're not so different. You're both dads and husbands and now both wise enough to appreciate every little thing in life and the wrestling business and the journey you walked -- and surviving that journey -- you go out there with each other and it's just perfect. It's perfect.

"All those things came together for me, and I just thought to myself, 'I don't think it gets better than that.' If you're looking for more, you're going to do that in everything in life. It's like chasing your tail. I didn't want that. I see other people not being happy, and being happy is important to me. I want joy in my life. That's why I got in the wrestling business, I liked it and it made me happy. So many times near the end, everybody looks unhappy. I didn't want that for me in my life."

As Calaway prepares for his own exit from wrestling after a years of competing while age was visibly starting to affect his performances, Michaels believes he will be able to find that same kind of contentment in this new phase of his life.

"I do. That's one of the things I sensed that time," Michaels said. "Like I said, I want that for him. It's one of the things that bums me out, that I didn't know. Mark has never struggled with anything, and if he has, I've never known because he keeps things close to the vest. Everybody's got their kryptonite, too. No matter how much everyone thinks someone has it all together, nobody does. Everybody has a chink in their armor. Every Superman has his kryptonite. I believe he can [be content], but some of that is on you as an individual to allow yourself to find contentment and peace in a situation.

"He's a smart, bright, intelligent man, and I believe that, yes, he will find it. All I know is that in these last few years, I've never wanted it for someone so badly like I do with him. Because, again, I feel like shit for not -- it's one of the things I always say to him when I see him. You know, 'Thank you so much for giving me that.' He didn't know he was giving me that, but he did. To me, that will be the greatest gift that dude or darn near anyone has ever given me, that feeling to be able to walk away from the wrestling ring and not struggle with it because I understand how unbelievably rare and special that is."

WWE will hold The Undertaker's Final Farewell on Sunday at Survivor Series. The event will air at 7 p.m. ET worldwide on the WWE Network.