10 WWE records that may never be broken

10: Undefeated streak at Wrestlemania: Undertaker - 21 - 0

Never again.

The career of Mark Calloway, better known as The Undertaker, is one of professional wrestling's most important and historic of all time. When he finally fell to Roman Reigns and took his first step into full-time retirement, wrestling fans of all ages knew they were seeing the end of a true legend.

The Phenom has enjoyed several World title reigns over the years and been the innovator of a handful of match concepts including Hell in a Cell, the Buried Alive match and the Casket Match.

In his more recent years, his career has essentially been built around his record at Wrestlemania. After earning himself a 14-0 undefeated streak in 2001, the company's writers started to realise how much of an impressive feat this was. Every year from then on, the story around Wrestlemania season would be whether anyone would be capable of ending the run of match victories.

The apex of the streak came when he faced Shawn Michaels at Wrestlemania 25 and 26 in two of the greatest matches in that event's history. By the time Wrestlemania 29 came around, fans really started to believe that the streak would never end and he would retire undefeated. That was not how Vince McMahon saw it, however, as the Beast, Brock Lesnar shocked the world by pinning The Deadman at Wrestlemania 30, officially ending the undefeated streak at 21 -1.

It's nearly impossible to imagine this record being broken. Most of the current roster has lost at least once at Mania, meaning they would have to start from scratch next year. Perhaps the company should never actually attempt to do this anyway, as this impressive record sets the Undertaker apart from everyone else in the company's history, which is where he probably deserves to be.