Undertaker vs Sting is being held back by one thing—the former's health.

Sting vs. The Undertaker is one of the biggest dream matches that hasn't happened in WWE. Many had hoped that the bout would finally take place when The Vigilante joined the WWE in 2014, but that never took place.

Unfortunately, Sting had to retire after suffering a neck injury during a match against Seth Rollins at Night of Champions 2015. In fact, retirement is exactly what's holding back this match, according to Dave Meltzer.

The 2016 WWE Hall of Fame inductee has stated multiple times that he's hoping to come back for one more match, delaying surgery that would end any chance of Sting being able to wrestle again. But given the age of both men (Sting is 59 this March, while Undertaker turns 53), and The Deadman also possibly retired, it's safe to assume this match will never really happen.

There was hope they'd face off at WrestleMania 31, but Sting faced Triple H, while The Undertaker faced Bray Wyatt. A year later, Sting formally retired and got into the Hall of Fame.

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Because of their dark, mysterious and vigilante personas, Sting and Undertaker became one of the most desirable matches ever. Many don't know that the two actually faced off in a 1990 WCW house show, where 'Taker was wrestling as "Mean" Mark Callous.

via wrestling-edge.com

Sting was the face of WCW, carrying the company to new heights in the '90s. The six-time WCW World Heavyweight Champion headlined many pay-per-views, and his Crow gimmick is widely considered to be one of the most iconic in wrestling. Because of his long-standing rivalry with the villainous New World Order, Sting became one of the most beloved stars of his time.

After Vince McMahon bought out WCW, Sting opted to not join the WWF and signed with TNA instead, fearing he'd be poorly misused by the creative team. A series of events just always kept preventing is match with 'Taker from happening.

But remember, Sting always said, "the only thing that's for sure about Sting is that nothing's for sure." At his Hall of Fame induction ceremony, he also said, "see you later." So if he does get cleared for one more match, maybe the dream match will finally happen.

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