The defensive line was one place USF absolutely couldn't afford a major injury. Unfortunately they likely have one after today's practice when Cory Grissom, the Bulls' most experienced defensive tackle, broke a bone in his ankle. Grissom will undergo surgery on Thursday and it's unclear how much time he will miss.

Without Grissom, there isn't much depth left at tackle. Elkino Watson and Luke Sager are the only tackles back with any kind of experience. Demi Thompson only played in two games in 2010 and missed all of last season with a back injury. Todd Chandler may be approaching washout status after redshirting two years ago and being shut down for academic reasons last year. And James Hamilton, the only other defensive lineman with enough size to play tackle, will be a true freshman this fall.

To make matters worse, Hamilton is the only lineman with enough size because Anthony Hill tore his ACL during the Green and Gold Bowl and won't play this season. The longer Grissom is out, the bigger this problem may get. No pun intended.

P.S. On the plus side, if Grissom can't play this year, he'd have a case for a sixth year of eligibility in 2013.