The Pittsburgh Steelers are 3-1 after the first quarter of the NFL regular season and, although the one blemish on their record likely still has fans’ feathers ruffled, the team seems to be moving in the right direction.

So it’s time to look back on the first-four games and assess the progress of the units involved. Today, we focus on the defense by position and then give out an overall grade to the group.

Cornerbacks

This group is really tough to grade for me. Why? They simply haven’t really been tested yet, and a large part of that is the success of the pass rush. However, Joe Haden was a great acquisition, and suddenly he and Mike Hilton have rejuvenated a sagging secondary — for now.

Grade: B+

Safeties

Injuries have kept this group from living up to the hype, but they’ve stayed afloat for the time being. Sean Davis has struggled early in this season, and both safeties, whether it be Mike Mitchell, Davis or J.J. Wilcox haven’t impressed in run support. Really bad angles have equated to big runs for the opposition.

Grade: C-

Inside Linebackers

The Steelers’ inside linebackers have gone as Ryan Shazier has gone. Shazier is turning into an all-or-nothing type of player, and that’s okay as long as you get the ‘all’ more than the ‘nothing’. In Week 3 vs. Chicago, Shazier came up empty more than anything else, but in Week 4 he showed up in a big way. Vince Williams has been as advertised so far this season.

Grade: B-

Outside Linebackers

Rookie T.J. Watt, Anthony Chickillo and Bud Dupree have been really good so far this season, and they’re a large reason why the Steelers currently rank second in the NFL in sacks. The trio holds seven of the team’s 15 sacks to date, and although they’ve struggled at times in run support, they’re making plays on a regular basis.

Grade: B+

Defensive Line

Cameron Heyward is having all All Pro year and, when he and Stephon Tuitt are both in the lineup, they’re the best 3-4 DE tandem in the NFL. Throw in Javon Hargrave and that’s one nasty 3-4 defensive front. With Tuitt’s injury, both L.T. Walton and Tyson Alualu provided quality depth at the end position, which was a huge bright spot. But the team has been gashed periodically by the run which keeps them from earning the ‘A’ grade.

Grade: B+

Overall Grade: B+