I don't know about MMA but I was screwing around in Judo today when I was paired against a big feller who was about 100 pounds heavier than me. We basically got within gripping range and he tried to aggressively grab my collar but I essentially stuck my wrist to his and redirected his arm every time he reached, it vaguely resembles Tai Chi push-hands. I was by no means playing seriously and it's not MMA but I thought I'd mention it for sh*ts and giggles
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