Free-agency review: Redskins

Most significant signing: Others landed bigger contracts, and might produce bigger stats, but Terrance Knighton is considered the game’s best nose tackle, and he gives the Redskins something they haven’t had: a stout run-stopper in the middle of their 3-4 defense. According to ESPN Stats & Information, the Redskins ranked 18th on yards per carry up the middle last season and were 25th on such runs on first down, when the nose tackle is more apt to be on the field. Meanwhile, Knighton’s old team, Denver, was second and fourth, respectively, in those categories. It’s not a coincidence. If the Redskins improve on early run downs, they can force tougher passing situations on later downs.

Most significant loss: LB Brian Orakpo. The Redskins attempted to re-sign their pass-rushing outside linebacker, but they did not want to go as far as Tennessee did (four years, worth up to $35 million). He has had three torn pectoral muscles since the final game of the 2011 season, but Orakpo has still been a good player when healthy (he had 38.5 sacks in his four full seasons). His loss means the Redskins will need to find another edge rusher. Ryan Kerrigan is solid on the left side and is coming off a 13.5-sack season, but Trent Murphy enters his second year as an unproven rusher on the right side. He has plenty of moves but not much explosion. The Redskins ranked 24th in the number of times the defense controlled the line on a pass, according to ESPN Stats & Information. Adding Stephen Paea and pairing him with a healthy Jason Hatcher will help inside, but they could still use more explosion off the edge.

Biggest surprise: Their inability to find a starting right tackle or, to a lesser extent, more help at safety. The Redskins did inquire about right tackles Derek Newton (re-signed with Houston) and Jermey Parnell (opted for Jacksonville). They do have Tom Compton and Morgan Moses there, but the former is better as a backup, and the latter is not only coming off a Lisfranc injury, but still needs more seasoning. At safety, the Redskins did sign Jeron Johnson and plan for him to start at strong safety. But this is still an inexperienced group with no starting free safety (they tried, but failed, to sign Antrel Rolle). It’s not surprising that the Redskins didn’t overpay any safeties -- they shouldn’t -- and their desire seems to be more about beefing up the front seven to offset issues in the secondary. But they still need to find a legitimate solution at safety.

What’s next: The Redskins will continue to seek good value in free agency, as they showed in the first week. They did not pursue some big-name players at areas of need because it did not fit their disciplined approach (they did not chase them last year, either). But, as stated above, they still must find help at right tackle and safety. They have told people they wanted to add two corners in free agency; they’ve already signed Chris Culliver. So that’s another area to watch, as is running back after they lost Roy Helu.