BJJ Black Belt Opens Up On Submitting UFC’s Sean O’Malley In A Grappling Competition

Robert Diggle is a BJJ black belt who has spent years competing at the highest levels of submission grappling. On a recent episode of the Simple Man Podcast, he gave some candid context around one of his more talked-about performances: the time he submitted UFC star Sean O’Malley in a grappling competition.

Diggle had already been through significant physical damage before the match even started. Earlier that same day, a competitor caught him in an unusual calf slicer.

“I didn’t believe it was going to work,” he told the hosts, “and I didn’t tap to it and it popped my knee pretty bad.”

He estimates the O’Malley match came roughly five minutes after that injury.

Even with a compromised knee, Diggle was still thinking strategically before stepping on the mat. His original plan was to secure a back take and look for a choke from back control, and his reasoning was calculated rather than technical.

“If I heel hook a UFC guy, people are going to be like you’re a d**khead,” he said.

The concern was less about the technique itself and more about the inevitable online reaction that would follow.

That concern turned out to be well-founded. After submitting O’Malley, Diggle found himself on the receiving end of a wave of comments from fans who argued the result was meaningless in the context of O’Malley’s MMA career.

“The same three st*pid comments again and again,” he said. “This is an MMA match, you wouldn’t have gone that well.” His response was equally direct: “It’s not an MMA match.”

Diggle acknowledged freely that O’Malley would have a clear advantage in a striking-based contest. He made clear he had no illusions about how that scenario would play out. But a grappling competition operates under entirely different parameters, and conflating the two was something he found consistently frustrating.