The defensive group on the Villanova roster that returns the most is the defensive line. Two of the three starters from last season return, as does an opening day starter from last season who returns from a knee injury. For Villanova to compete next season, they will have to be solid on the defensive front, and with an inexperienced linebacker corps, the defensive line will need to get to take increased initiative to get after the ball. In the offseason, former Maryland line coach Dave Sollazzo was hired to coach the position, so there's another added dimension of change to a team in transition. While the starters are mostly back, this is still a position where the depth is very young (for the most part).
Defensive End: The starters at defensive at defensive end are firmly entrenched, and both have a full year of starting experience under their belts. Junior Marlon Johnson started the entire 2009 at defensive end and one game the next season, the opening game of the season in 2010, a game where he blew out his knee. Johnson has good size and the athleticism to drop back in coverage, but his pass rushing skills never really showed. It should be noted that he was a starter on the stingiest run defense in school history, so there is that. Starting at the other defensive end position should be sophomore Rakim Cox, who started 13 games a season ago. Cox is big and athletic, and definitely looks the part and he should improve on a solid, but not great performance his freshman year. It would be nice if he can build on his previous season and pair up with Johnson to get after the quarterback.
The primary backup to both defensive end spots will be sophomore Keelan Malone. In a bit role last season, Malone was decent. I wouldn't expect the starters to leave the field very often, and Malone may only get regular playing time in sub packages or in the case of injury. Behind Malone is a bunch of guys you probably don't want to see including true freshman including Jordan Hunter and Reggie Paris.
Nose Tackle: A revelation last season as a true freshman, Antoine Lewis will begin his sophomore season at nose tackle after starting all but one game last season at defensive end. This should be a good fit for Lewis as nose is his natural position. I suppose in a real pinch, he could move back to defensive end, but that's a scenario i do not want to think about.
Backing up Lewis will be a combination of junior Joe Makoid and freshman Pat Williams. Neither of them will see the field too much in the base defense unless there is a significant injury to another player on the line.
As you can see, this group could be quite good, but there is almost no room for injury. Luckily, there are only three defensive lineman in this scheme and not five, making an injury somewhat less likely