Bo Nickal has made an impressive transition from being an elite wrestler to a contender in MMA, and now he’s just been promoted to purple belt in BJJ too. The promotion has come in the wake of one of the biggest wins of Nickal’s career so far; a third-round knockout of Rodolfo Vieira at UFC 322. Although the finish came from strikes in the end, Nickal also made good use of his grappling …