Big 12 hires Brett Yormark as commissioner: Executive at Jay-Z's Roc Nation to take over in August | CBS Sports Headlines Big 12 hires Brett Yormark as commissioner: Executive at Jay-Z's Roc Nation to take over in August Yormark has more than two decades of experience in sports but none … Continue reading Big 12 hires Brett Yormark as commissioner: Executive at Jay-Z's Roc Nation to take over in August