Oklahoma State's defensive coordinator has announced he's not returning next season. Derek Mason has been with the Cowboys for just one season. Prior to that, he was the head coach at Vanderbilt. He posted on social media that he planned to take a sabbatical from college coaching after 30 consecutive seasons. He said he looked forward to spending time with his family, to rest and reflect on opportunities within the game he loves. He went on to thank the university, coaches and fans for their support.