Given the stakes, Rose couldn't afford to let emotion get in the way of the match, and she didn't hold anything back against her former friend.
The Golden Goddess connected with a series of running knees before landing her Bed of Roses finishing move. Still not content, she hit Deville with one more running knee to put her away for good.
The Pride Fighter left the arena in tears, but Otis rushed to the ring and celebrated with his girlfriend, Rose.
The two women have been at odds since before WrestleMania 36 when Rose discovered her ex-friend and Dolph Ziggler were working together in an effort to ruin her relationship with Otis.
That resulted in a rivalry pitting Rose and Otis against Deville and Ziggler, but when The Showoff left the blue brand for Raw, it seemed the feud between the ex-Fire & Desire teammates had run its course.
All of that changed on the July 31 edition of SmackDown, though, when Deville targeted Rose backstage while she was getting ready for a date with Otis. She drew on her face with lipstick and began cutting her hair off.
The Pride Fighter even turned on some clippers and was about to shave Rose's head, but Otis, Tucker and some backstage personnel stepped in to stop her.
The Golden Goddess then attacked Deville on an ensuing episode of SmackDown, proving she wouldn't allow her former pal to push her around.
Rose was so angry over what Deville did to her that she laid down a surprising challenge. She called for her to accept a Hair vs. Hair match at SummerSlam, and given the heel's desperate attempts to make Mandy "ugly," she accepted.
They reversed course the following week, however, as Deville felt the stakes weren't high enough and challenged Rose to a Loser Leaves WWE match instead.
Deville and Rose go back many years, as they first met when they were contestants on Tough Enough in 2015. They both earned WWE contracts and worked their way through NXT before debuting on the main roster together in 2017.
They were part of the Absolution stable with Paige, but a career-ending injury forced the Briton to retire and the faction to end after only a few months. Even so, Deville and Rose stayed together as Fire & Desire.
They enjoyed some success as a tag team and seemed to be a good pairing, but since they both have the potential to be big stars individually, it was probably the right time to break them up earlier this year.
Rose and Deville impressed Sunday on a big stage, and while the loser will apparently be out of the picture for now, there is little doubt she will be back at some point.
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