Whether a team runs a 3-4 or 4-3 defense, there will be plenty of quality run stoppers and pass rushers available in free agency that fit both schemes. With one of the best interior linemen in all of football hitting free agency and one of the best defensive ends also hitting free agency, there’s going to be a few front sevens making massive improvements.

10. Dan Williams

With the injury to fellow defensive lineman Darnell Dockett this season, Williams saw his snap count almost double from last season to this season. Williams certainly took advantage of this increase in snaps. As a pure nose tackle he didn’t create much of a pass rush, but was extremely stout against the run. He’s the kind of guy you want anchoring the middle of your defensive line.

9. Cory Redding

Redding is at the tail end of his career and likely doesn’t have too much left in the tank. However, he was still able to create a good interior pass rush this season for the Colts. Redding had four sacks, eleven hits on the quarterback, and 22 hurries. While his pass rush is the best part of his game, he still has the strength to maintain his gap responsibilities in the run game. He is also quick enough to shoot gaps and disrupt plays in the backfield when he’s asked to do so.

8. B.J. Raji

Last preseason Raji tore his right bicep and missed the entire 2014 season. Assuming Raji comes back completely healthy in 2015, he’ll be a force to reckon with again. Raji has the size and strength to anchor the middle of any defensive line and the quickness to get off the ball and pressure the quarterback.

7. Nick Fairley

Fairley had one of the most productive seasons of his young career in 2014. While his numbers might not bare that out, it certainly showed when watching him in the games. Fairley is an interior lineman who can do it all. His best asset is his pass rush, but he’s still a solid run defender. His biggest problem when defending the run is that sometimes he takes himself out of plays when he penetrates too deep and makes it easy for his blocker to take him right out of the play.

6. Trent Cole

Cole is a natural 4-3 defensive end, even though he played as a 3-4 outside linebacker this past season. He has some impressive pass-rush skills for his age and position. Playing as an end he’s able to use his hands much more than when he’s an outside linebacker, and that’s a distinct advantage for Cole. He has very good pass rush skills and at the same time has very solid run stopping skills as well.

5. Henry Melton

Melton split snaps this year and will be looking for a place to land where he won’t have to do that. Even while splitting snaps he was able to generate a very good pass rush. While his pass rush was very good, his run defense left something to be desired. If he is able to fix his problems with stopping the run this offseason, he could be a giant steal for whoever is able to sign him.

4. Terrance Knighton

While Knighton might not look very versatile, he allows a defense to play many different ways. He can play a one-gap or a two-gap technique and he plays both extremely well. For his size, he gets into the backfield to disrupt plays awfully quick. On run plays he has the strength to hold just about any offensive lineman at bay and shed him to make the tackle. He’s also exceptional at not giving up ground on double teams.

3. Brandon Graham

While Graham played this season as a 3-4 outside linebacker, he’s better suited for his natural position as a 4-3 defensive end. Graham is a tremendous pass rusher who racked up six sacks, eight quarterback hits, and 39 quarterback hurries. Those are good numbers by themselves, but they’re even better when you take into consideration that he was splitting snaps all season. If he lands on a team where he can be a three-down lineman, he can be a breakout player in 2015.

2. Greg Hardy

While Greg Hardy only played in one game this past season due to legal issues off the field, he is still one of the most gifted players in the league. Hardy's pass rush off the edge is almost unstoppable and if he’s not sacking the quarterback himself, he’s creating enough pressure to change the play or helping one of his teammates get a sack. For such an aggressive pass rusher his run defense is strong. His biggest problem has been missed tackles in the open field.

1. Ndamukong Suh

Suh is the best interior lineman in the entire NFL. He can do absolutely everything on the defensive line and did just that this past season. The Lions had Suh line up for a significant amount of snaps at every position on the line. Not only is he able to do that, he’s able to do it at an elite level at every single position. If he’s not directly making the play, he’s having a major impact on disrupting it somehow.