Per Mike Tomlin post-game press conference:
David Johnson knee injury is severe. Sounds like he will miss the entire 2012 season.
Mike Adams also suffered a knee injury, but it is less severe.
Jonathan Dwyer suffered an AC sprain in his shoulder.
Rainey also tweaked a knee, but was able to return to the game.
Full break down of the Steelers first preseason game will be avaliable tomorrow.