By Philip O'Connor
LAS VEGAS (Reuters) - Champion Khabib Nurmagomedov ended Irish fighter Conor McGregor's attempt to win back the UFC lightweight title when he sealed a brutal submission victory with a rear naked choke hold in the fourth round on Saturday.
The win prompted a mass brawl to break out in and around the cage, with a red-shirted fan landing several blows on McGregor before security intervened.
Nurmagomedov dominated the fight, taking McGregor down early and smothering him with his wrestling skills and, behind on the judge's scorecards, the Irishman was left with no choice but to throw a succession of punches in the third round.
Exhausted by the fourth round, Nurmagomedov took the former two-weight champion's back and sank in the choke to stretch his professional record to 27-0 and hand the Irishman his second defeat in the UFC.
(Editing by Greg Stutchbury)