11:13 AM ET 03.27 | Texas A&M Aggies quarterback Johnny Manziel has been the subject of a lot of criticism this offseason because he doesn't seem to grasp the fact that winning the Heisman Trophy results in living under the microscope and being put to a higher standard. Manziel has erratic off-the-field behavior and has been using social media to get back at fans that have called him out. As a Heisman winner, you have to be better than that. Manziel may eventually understand that, but for now he is shutting himself off from the outside world as he prepares to focus on the upcoming season. While speaking with Mark Schlabach of ESPN, Manziel said that he has issued himself a Twitter ban and will be stepping away from social media for the foreseeable future.