Rey Mysterio was stabbed in the back by his own son Dominik at WWE's Clash at the Castle pay-per-view. That's right, it finally happened, and it happened at the Principality Stadium in Cardiff, Wales on Saturday, September 3.It all went down following the thrilling conclusion to the fourth match of the main show, in which Rey and his former Ruthless Aggression rival Edge joined forces to defeat the dastardly Judgement Day (Finn Balor & Damian Priest). After the bell, Rey and Edge celebrated in the ring with Dominik, who had supported his father from ringside throughout the match ... but the celebrations were short-lived.

In a turn of events (which everyone saw coming) Dominik kicked Edge below the belt while the WWE Hall of Famer's guard was down. An Irate Rey chastised his son and tried to shake some sense into him, but to no avail. A switch had been flipped in Dom, and he sealed his turn to the dark side by delivering a brutal clothesline to his old man, almost decapitating the legend in the process.

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As the events described above unfolded, the beaten members of Judgement Day looked on in amusement -- although Dom didn't join them. Instead, the youngster walked slowly back up the ramp as his father and Edge regained their senses in the ring. The segment drew to a close with Edge and Rey in an embrace as they soaked up the adulation of the WWE Universe's UK contingent.

Back in July, Rey and Dominik commented on the idea of feuding with each other during an interview with BT Sport.

We actually talked about that during his first couple of weeks of training,” Rey said. “I remember sitting down with him, and telling him … ‘Could you imagine if you started working and then we teamed up and eventually, you know, whether I turned on you or you turned on me?’ Yeah, that would be cool …"

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