Long before The Undertaker debuted in WWE the NWA had an intimidating tag team called the Skyscrapers.
The team was comprised of the 6'9" Sid Vicious (later known as Sid Justice in WWE) and the 6'8" Dan Spivey.
Together, they formed one of the most physically imposing teams in the business.
When Sid Vicious was injured, though, management knew that they needed another big guy to replace him.
Along came the Undertaker. At 6'10" and wrestling as "Mean" Mark Callous, he was the perfect replacement. The Skyscrapers were good enough to get themselves involved in a feud with the Road Warriors.
Under the guidance of Paul Heyman, the Undertaker started moving his way up the NWA ladder. He even earned himself a shot at Lex Luger's NWA United States Heavyweight Championship at the 1990 Great American Bash.
For some odd reason, though, management decided not to resign the Undertaker when his contract ended.
Of course, that decision helped to change wrestling history forever.