Mixed martial arts in the United States saw it's second death in the cage this past weekend, with lightweight fighter Michael Kirkham suffering head trauma during a bout in South Carolina and dying soon after. It was Kirkham's pro debut, but he had six amateur fights under his belt, and by all accounts this was a fully-sanctioned and regulated event. This is a tragedy for all involved - for Kirkham and his family, of course, and for his opponent, who simply did his job and now must forever live with Kirkham's blood on his hands. The likelihood of injury is ever-present in MMA, yet no one expects death to occur, and sadly, it infrequently does. Everyone will always remember Sam Vasquez for being the first fighter to die in a sanctioned US bout, but we should never forget Michael Kirkham. To do otherwise would dishonor the sport he died for.