HDNet, Mark Cuban's high-definition network, is entering the mixed martial arts arena with a new business dubbed HDNet Fights. The first event is Oct. 13 at 7 p.m. at the American Airlines Center in Dallas, with the on-air debut set for Oct. 19. Cuban has hired former UFC champion Guy Mezger to head up fight operations for the new company. While HDNet has aired MMA events before, this will be the first venture into the MMA business for Cuban and HDNet. HDNet also is debuting a new series, "Inside MMA," hosted by Kenny Rice and former MMA fighter Bas Rutten, tonight at 9:30 p.m. ET.