
20. Jon Gruden
A coach should set an example for his athletes. But Gruden betrayed them by being a horrible excuse of a human being. An investigation into Washington’s dirty dealings revealed the truth about the Raiders’ coach. He exchanged dozens of emails with Washington GM Bruce Allen.

Gruden used appalling and derogatory language in the emails. He made homophobic references to different athletes and exchanged topless pictures of cheerleaders. It was deplorable and ultimately cost him his job. Las Vegas fired him because he made his position untenable (via Sporting News).