Freaking pre-season games man. They should go down to two pre-season games and not play the starters period. Those games should be strictly for back ups (and they should only be seeing minimal time), rookies (high draft picks/same applies as the back ups), bubble players and others they know are getting cut.
This ofcourse should all towards this 18 games season proposal. Go to 18 games with a additional bye week, increase the rosters by 7 players at least, increase their pay ofcourse and go to only two pre-season games as I mentioned above. No need for the starters to be playing in preseason games at all!