The biggest concern early is the ability of the defense to stay strong through an entire game. In the New Mexico game, things snowballed in the second half. This led to the defense playing an extremely large number of downs. Some things, like the roughing the punter penalty, were outside of the defense's control. However, for the most part, the defense has the most control over how many plays they play. This will be the case unless the offense suddenly starts going three and out on a regular basis. The biggest problem was the conversion of long third downs along with fourth down conversions. These conversions allowed New Mexico to mount several sustained drives. The good news is that most teams won't be as aggressive on fourth down. The other concern on defense is depth. The lack of depth on the defensive line is a major concern right now. If any injuries force a player to miss a game, it will require some work to make up for the loss. If this were to happen, look for someone like Mike Smith to move onto the defensive line to fill in at an end spot.
There are also a number of nice positives. The first is the play of the linebackers. The linebackers have been given more freedom, and they're taking advantage of it. Red Raider fans already knew how good John Saldi was, but Brock Stratton and Mike Smith are also playing good football. Smith has shown adequate speed to the outside, but his main strength is his ability to clog up running lanes. Brock Stratton has been outstanding, making a number of nice plays to stop big gains against New Mexico. This group is easily the best part of the Texas Tech defense. The defensive line has played solid football. They're not necessarily making huge plays, but they aren't making huge mistakes either. This unit will continue to improve throughout the season. The secondary has also been solid. The safeties have been making plays, while at the same time preventing big plays from happening. The lack of big plays allowed by the secondary is a great improvement over last season. The cornerbacks are inexperienced, and it shows. The good news is there is plenty of talent to call on at the position.
Overall, the defense has shown some nice improvements. They are forcing more turnovers and preventing big plays, but they need to play a little better in order to stop long drives. They have a lot of room for improvement, but they can be a good defense once all of the talent is being fully utilized. I'd look for major improvements in the weeks leading up to conference play.