With the new redshirt ruling allowing participation in up to and including 4 games, I think we'll see quite a few more true freshmen get a shot, at least in garbage time.
All listed in order of importance/likelihood:
Impact players, burning RS:
One of Craddieth/Brents/Johnson will win a starting corner role
Tracy
Significant contributors (meaningful playing time) without burning RS:
Nixon - If and only if his special case is included in the 4 game allowance for his required RS year
Other one or two of Craddieth/Brents/Johnson
Geil - We seem to always need a #4 back at some point in the season
Linderbaum
Ragaini
Doyle
Jenkins