Only one Superstar can run the yard in WWE, and at The Ultimate Thrill Ride, WrestleMania 33, the world will find out whether that distinction belongs to The Undertaker or Roman Reigns.

The showdown between The Phenom and The Big Dog, now confirmed for tomorrow, brings into conflict the most dominant force in WrestleMania history and arguably the most powerful competitor in recent memory.

The Undertaker has been WWE’s unofficial gatekeeper, enforcer and overseer for more than a quarter-century, regardless of his championship status at any given time. However, after Reigns ousted The Deadman from January’s Royal Rumble Match and then told the imposing legend that WWE is now his yard on the March 6 edition of Raw, it became clear that The Undertaker took issue with Reigns’ emboldened outlook. The evidence came in the form of a ring-shaking chokeslam that nearly put The Big Dog through the canvas.

The Deadman made a surprise appearance on Raw to remind The Big Dog whose yard he's standing in.

Reigns has achieved a stunning number of accolades in WWE at a breakneck pace, but defeating The Undertaker at The Show of Shows would launch him into WrestleMania infamy and solidify his status as “The Guy.” Over the course of his 24 WrestleMania appearances, The Deadman has lost only once, against Brock Lesnar in 2014, and as the WWE Universe knows all too well, The Undertaker takes on an almost supernatural power when competing at The Showcase of the Immortals.

Can Reigns usurp WWE’s Phenom at WrestleMania, or will The Undertaker prove he is still the biggest dog in the yard? Find out when The Ultimate Thrill Ride, WrestleMania 33, streams live on WWE Network tonight, at a special start time of 7 ET/4 PT.