There's no doubting the Undertaker's impact in pro-wrestling, as the Phenom celebrates his 25th year in World Wrestling Entertainment this Sunday at Survivor Series.

However, well before he became arguably the greatest WWE Superstar of all time, Mark Calaway was like any other young pro-wrestler, trying to find his character's footing and a consistent place in the storylines ... but for then-rival company World Championship Wrestling.

In a column for Fox Sports, former WWE announcer Jim Ross remembers a time in the early 1990s when Calaway was wrestling under the name "Mean Mark Callous" and his contract was coming up for renewal.

Ross, who was also working for WCW at the time, remembers him and Jim Cornette being big on keeping the 6 foot 9 300-pounder, but being opposed by a wrestling legend in his own right in none other than Ole Anderson.

"Ole Anderson was the booker — ultimately in charge of the talent roster — and he felt that Mark 'would never draw a dime,'" Ross remembers. "Ole and I disagreed on this matter, but I lost the argument as many did to the combative wrestler.

"Ole generally had a good feel for who had 'it' and who didn't," Ross continued, "but it's easy to say 25 years later even Ole Anderson can make a mistake."

Oh, yes, he can ... a big mistake. The error to not re-sign Calaway turned into him taking his talents to WWE, developing the Undertaker as his character and being a pro-wrestling force for a quarter century. JR even calls him the "Clint Eastwood" of the WWE.

In subsequent years, when huge names like Hulk Hogan, Kevin Nash, Scott Hall and Bret "The Hitman" Hart jumped ship from WWE to WCW, the Undertaker put the flag in WWE and remained a cornerstone of the company — something he continues to be to this day.

To celebrate his 25 years in the company, the WWE even made this video, offering 25 numbers that define the Dead Man.

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