It's hard to disagree with fans who say Undertaker's past the prime of his career, as recent matches at WrestleMania, as well as one-off appearances, have shown. Also known as Mark Calaway, Undertaker has been in the WWE since the early '90s and been showcased in over a dozen WrestleManias. However, at 55-years-old, it's hard to expect the same in-ring quality from him now as he had in the Attitude Era.

It's why so many have made calls for him to retire, especially after his dismal showing against Roman Reigns at WrestleMania in 2017. Granted, he did impress in this year's bout against A.J. Styles, it was still an edited film, so he had time to rest. But, courtesy of the WWE docuseries, The Last Ride, a fellow superstar makes it clear why Undertaker can't retire easily and why the public needs to ease up.

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One of the most poignant moments comes about halfway through the hour-long premiere when Shawn Michaels is ribbing Undertaker backstage at the Hall of Fame ceremony prior to the Reigns clash. On camera, Michaels -- who's worked extensive programs with the Dead Man over the decades -- wonders if Undertaker knows his body's limits. And this is where Edge ties the retirement angle in to Undertaker being an institution that we simply must respect.

"I think that's the danger. It's that you don't know sometimes," Edge said, comparing it to Brett Favre's time with the Minnesota Vikings when he was past his prime. "It's still there but it might not be there as much. So when is the time? And is it fair for anyone to tell that person when it's time with that kind of a career behind them."

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It's a great point, because not only has Undertaker built the Show of Shows, he's known as one of the premier global wrestling icons who helped Vince McMahon establish a powerful brand. The fact he still fights at WrestleMania and the way the world reacted when Brock Lesnar broke his streak in 2014 at 21 says it all. Undertaker is an immovable pillar of the industry. It's why Undertaker is the only person who can call time and retire. Not even his boss will dare cross that line, out of respect, friendship, professionalism and fraternity. He's toiled and bled, so he's earned the right to go out on his terms and on his schedule.

"They have carte blanche to say when it's time; therein lies the difficulty," Edge admitted, which also ties into him returning to action this year after a career-threatening neck injury in a grueling Last Man Standing match against Randy Orton. Now, he's not as decorated as Undertaker in terms of a brand, but Edge has also won almost everything there is to win, so he's speaking from a personal perspective. And it connects to people who don't want to retire because they love their job.

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The episode suggests Undertaker can walk away from wrestling any time, and while he says once McMahon calls, he'll answer, his wife Michelle McCool knows he looks forward to it once a year without anyone having to call. He might joke to his peers that just when he's out, execs pull him back in. But it's not about a pay check or ego: the Dead Man loves the business and he thinks he's doing fans a disservice if he doesn't come out. In fact, he wants to keep pushing his body, but admittedly the way he's trying to impress new fans isn't smart because while his mind is there, physically he's not.

Edge did make it clear this psychological aspect is hard to break because you do feel a sense of duty and like you owe it to the company to return. Of course, these guys feel like they owe it to themselves as well, because hearing the rapture of the crowd is a big reward. "He's Undertaker to everyone, so that is an expectation you almost have to live up to in people's eyes," Edge said as he closed out the segment, which does suggest that as long as a small portion of fans do want the Dead Man or the American Badass, he will be coming back for more.

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