Antoine Bethea: Eric Mangini defense will cause confusion for 49ers' opponents

The San Francisco 49ers are in the midst of installing their first new defense since 2011. That year, Vic Fangio joined Jim Harbaugh in moving from Palo Alto to Santa Clara. While Harbaugh had oversight over the entire team, Fangio effectively was the head coach of the defense. The group had talent prior to Fangio's arrival, but his coaching staff helped that unit take several huge steps forward.

Now, Eric Mangini is installing his defense, and naturally the team's defensive leaders are getting questions about it. Safety Antoine Bethea met with the media last week, and he had some interesting comments about the developing defense:

"Coach Mangini's thing is that we're going to cause confusion. The opposing offense won't know what we're going to do each down. That could be bringing pressure or dropping eight in coverage but it's all about keeping the offense on their heels.

"That means a lot of movement and everyone having to know what everyone else is doing. It could be different people doing different jobs. Everybody just knows what we have to do. It's going to be fun."

Naturally creating this kind of confusion raises the issue of confusion amongst 49ers defenders. Bethea talked about the importance of OTAs, studying the playbook and getting as many repetitions as possible. One problem with that is there are several players dealing with injuries that are unable to fully participate. Defensive linemen Darnell Dockett and Glenn Dorsey are recovering from ACL and biceps injuries, respectively. Defensive back Jimmie Ward is recovering from his foot injury, while cornerback Tramaine Brock was not participating in the Thursday OTA open to the media. And on the non-injury front, Arik Armstead is unable to join the team until after his finals end in June.

Dockett and Dorsey are not nearly as concerning as the rest in terms of getting up to speed, but it still is something to track as the team moves toward training camp and getting ready for the upcoming regular season. There is a lot of intriguing talent on the defense, but if they are in a position where they are stuck thinking too much and not simply reacting, it will create some problems. Of course, if the defense can nail this down in reps now and in training camp, they potentially start to think less, and react more (if that makes sense).