According to TMZ , Manziel, who left the game of football after a string on personal issues, is “dead serious” about making an NFL comeback and has hit the gym in hopes of getting another shot in the league. Could the Miami Dolphins be a potential landing spot for the embattled quarterback? If the 24-year-old can stay sober and show he has made drastic strides in changing his personal life and his image, it is possible that a team or two could consider adding Manziel to its roster.