The Indianapolis Colts began their offseason makeover under new general manager Chris Ballard on Thursday.
"D'Qwell is a consummate professional," coach Chuck Pagano said in a statement. "The way he approaches the game is second to none. His leadership and mentorship provided a valuable example for the younger players on this team. We are grateful for all of his contributions to the organization and wish him the best."
Jackson signed in Indy in 2014. He had one year remaining on his contract. Cutting the linebacker saves the Colts $5.5 million of salary-cap space, per OverTheCap.com
The 33-year-old Jackson earned 366 tackles in three seasons with the Colts, leading the team in his first two years. Jackson was suspended the final four games of the 2016 season for violating the NFL's policy on performance-enhancing substances.
While he's been durable over the latter stages of his career, Jackson's play fell off precipitously. Pro Football Focus ranked him 80th of 87 qualifying linebackers in 2016.
Ballard's focus heading into free agency and the 2017 draft will be to stockpile an aging, porous defense that has gotten worse throughout Pagano's tenure in Indy.