#1 Backstage after WrestleMania 34 after his title match against Roman Reigns
Of all the incidents on this list, this one was the most recent. It took place backstage after WrestleMania 34. The main event saw Roman Reigns challenge Brock Lesnar for the WWE Universal Championship. The shocking result saw Brock Lesnar pin a bloody and beaten Roman Reigns to retain his title.
What happened backstage is more interesting. As we can see, Lesnar was clearly unhappy about something as he went backstage. The video shows a pissed off Brock walking into Gorilla Position. As he passed where Mr. McMahon was sitting and looking at the monitor, Lesnar just chucked the WWE Universal Championship at him disrespectfully and walked away. We can see Mr. McMahon replying to Lesnar's action with an expletive.
Corey Graves deleted his Tweet! More details HERE.
We don't know what triggered Brock Lesnar's reaction in this situation but he certainly lost his cool.