This season has seen many great defensive players retire, whose job it was to get past the opposing offensive line [VIDEO] or to shut down opposing offensive weapons [VIDEO]. Oddly enough most of the defensive players that retired from the NFL this off-season have been linebackers.

Defensive line

Terrance Knighton (2009-15) played in the NFL for 7 seasons as a defensive tackle. He started his career with the Jacksonville Jaguars where he played for 4 seasons. He then went to the Denver Broncos and played nose tackle for two years. After little interest in free agency, he played for the Washington Redskins in 2015. He signed with the New England Patriots in 2016 but got released before the season started, so he did not play last year.

Knighton finishes his career with 245 tackles, 14 sacks, 3 forced fumbles, 2 fumble recoveries and 2 interceptions.

Linebackers - part 1

Zachary Orr (2014-16) played in the NFL for 3 seasons, all with the Baltimore Ravens. After spending two seasons as a backup, Orr became the team's starting weak-side linebacker this past season. He made the All-Pro Second Team, but suffered a neck injury in week 16. He retired because of the injury after an MRI showed he has a congenital neck/spinal condition. Orr finishes his career with 158 tackles, 1 sack, 1 forced fumble, 2 fumble recoveries and 3 interceptions.

DeMarcus Ware (2005-16) played 12 seasons in the NFL and was one of the most feared pass rushers to ever play the game. He played his first 9 years with the Dallas Cowboys and the last 3 with the Denver Broncos.

In his career Ware made 9 Pro Bowls, 4 All-Pro First Teams, 3 All-Pro Second Teams and was part of the Broncos Super Bowl 50 team. He is the Cowboys all time leader in sacks and forced fumbles. He also has the 8th most sacks in NFL history. Ware finishes his career with 659 tackles, 35 forced fumbles, 8 fumble recoveries, 3 interceptions and 1 defensive touchdown.

Chad Greenway (2006-16) played 11 seasons in the NFL, all with the Minnesota Vikings. He missed his entire rookie season after tearing his ACL, but was relatively healthy the rest of his career. In his time with the team, Greenway was a 2 time Pro Bowler and make 1 All-Pro Second Team. Greenway finishes his career with 1,101 tackles, 18 sacks, 8 forced fumbles, 11 fumble recoveries, 11 interceptions and 2 defensive touchdowns.

Linebackers — part 2

A.J. Hawk (2006-16) played 11 seasons in the NFL, spending the first nine with the Green Bay Packers. He then spent one season with the Cincinnati Bengals and was with the Atlanta Falcons last year.

Hawk is the Packers all time leader in tackles and was a member of their Super Bowl XLV team. Hawk finishes his career with 950 tackles, 20 sacks, 4 forced fumbles, 5 fumble recoveries and 9 interceptions.

James Laurinaitis (2009-16) played in the NFL for 8 seasons, 7 of those with the Rams. He was the man in the middle for the Rams never missing any of the 112 games the team played. Laurinaitis left the Rams as their all time leading tackler. He played last season for the New Orleans Saints, but his season never got on track due to injuries. Laurinaitis finishes his career with 853 tackles, 16.5 sacks, 1 forced fumble, 8 fumble recoveries and 10 interceptions.

Stephen Tulloch (2006-16) played in the NFL for 11 seasons. Tulloch spent his first 5 seasons with the Tennessee Titans and then went to the Detroit Lions for five seasons. He spent his final season in the league with the Philadelphia Eagles. Tulloch finishes his career with 949 tackles, 14.5 sacks, 3 forced fumbles, 12 fumble recoveries, 5 interceptions and 1 defensive touchdown.

Secondary

Jerraud Powers (2009-16) played in the NFL for 8 seasons as a cornerback. He started his career with the Indianapolis Colts and played there for 4 seasons. He then spent the next three years with the Arizona Cardinals and last season with the Baltimore Ravens. Powers finished his career with 410 tackles, 3 sacks, 3 forced fumbles, 4 fumble recoveries, 13 interceptions, 75 pass deflections and 2 defensive touchdowns.