Yahoo Sports reports: As the NFL season approaches, there are a number of big-name players still available as free agents, and one of those names is former Cincinnati Bengals and Houston Texans running back Joe Mixon. But why is Mixon still a free agent in mid-June? Joe Mixon’s Health Is Still a Complete MysteryTo quickly answer the question of why Mixon is still a free agent, it’s simple: his health and injury status.