Morrison was a last-minute replacement for Keith Lee, who was ruled out due to an injury.
Lashley sidestepped an attack by The Guru of Greatness, who had taken a crutch MVP was using outside the ring, and locked in the full nelson. Unfortunately for him, the crutches came back into play as Riddle delivered a pair of big blows to send the champion to the outside.
From there, Riddle hit the BroDerek on Morrison for the win.
Lashley and Riddle have been at odds for several weeks, but even after The All Mighty defeated his rival in a U.S. title match on Raw in January, The Original Bro kept pushing for another opportunity.
Lee entered the fray on Feb. 8 when he beat Riddle in a singles match on Raw and established himself as a contender for the United States Championship.
Following that match, both Riddle and Lee were jumped by Lashley and The Hurt Business, which put The Limitless One's availability for the Elimination Chamber pay-per-view into question.
The former NXT champion did not appear on Monday's go-home edition of Raw, and the announce team said he had suffered injuries as a result of the attack the previous week, making it unclear if he would be able to wrestle at the PPV.
Riddle got some momentum on his side on Monday, when he and Lucha House Party beat Hurt Business members MVP, Cedric Alexander and Shelton Benjamin in a six-man tag team match.
Sunday marked perhaps Lashley's biggest challenge since becoming United States champion in August, as he was in the middle of a dominant run entering Elimination Chamber.
The All Mighty had run through no shortage of formidable challengers, including Apollo Crews and Titus O'Neil before having to deal with two tough customers in Riddle and Morrison.
Lashley and Riddle are two of the best midcarders WWE has to offer, and they both have the ability to challenge for a world title in the near future.
Despite his win, Riddle likely won't be in the world title picture any time soon, but it could open the door for Lashley to move up while The Original Bro transitions into a singles feud—perhaps with a returning Lee—heading into WrestleMania 37 on April 10-11.
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