Edge was forced to officiate the match after Bryan inadvertently hit the referee with his running knee finisher.
Reigns took advantage of the situation and delivered a Spear to The Yes! Man, but The Rated-R Superstar only made it a count of two before the challenger kicked out.
However, Edge crossed the line after Bryan accidentally hit him with a steel chair.
The challenger had the LeBell Lock applied as Reigns was tapping out. No official was around to ring the bell, though, and The Rated-R Superstar attacked both men with the chair in a fit of anger.
That allowed Reigns to crawl over and make the pin.
Ahead of his WrestleMania match, Edge served as the special enforcer for Sunday's bout after beating Uso to earn that right.
Reigns and Bryan have quite a bit of history, but their rivalry was truly rekindled at Elimination Chamber when the latter won a Chamber match to earn a universal title opportunity against The Tribal Chief that same night.
Rather than giving him time to recover, Reigns faced Bryan immediately after the Chamber match. The challenger caught The Tribal Chief in a Yes Lock and came close to pulling off a massive upset, but Reigns broke out and beat an exhausted Bryan in what ended up being a short match.
Reigns bragged about his dominant victory on the next episode of SmackDown, but Bryan called him out for taking the easy route. He then challenged Reigns to a universal title rematch at Fastlane, but Uso stepped in and said Bryan would have to go through him first.
Bryan and Uso fought to a double count-out, but the former was given one more opportunity to earn a title match if he could beat Uso in a subsequent steel cage match.
He went on to defeat Uso in the cage by making him tap out to the Yes Lock, meaning Reigns would have to put the Universal Championship on the line one final time before WrestleMania on April 10-11.
Sunday's match was reminiscent of a previous encounter between Reigns and Bryan in many ways, as they faced off in the main event of Fastlane 2015.
That match was for the WWE Championship No. 1 contendership, with the winner earning the right to face Brock Lesnar at WrestleMania 31. Bryan pushed Reigns to the limit in that match, but it was The Big Dog who prevailed and went on to challenge The Beast Incarnate.
At Fastlane 2021, Reigns kept his title run intact, and he ensured that a match against Edge will happen at The Show of Shows.
It isn't completely outside the realm of possibility that Bryan could find his way into the match and make it a Triple Threat, but for now, Reigns vs. Edge is on.
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