OWINGS MILLS, Md. -- The Baltimore Ravens have fired defensive coordinator Don "Wink" Martindale with one year remaining on his contract, a source told ESPN's Adam Schefter on Friday.

This surprising shakeup represents the first move made by the Ravens since they lost six straight games to end the season and failed to make the playoffs for the first time since 2017.

Ravens coach John Harbaugh issued a statement Friday saying he and Martindale "agreed to move forward in separate directions."

"We have had a great run on defense, and I am very proud of what has been accomplished and the work he has done," Harbaugh said in his statement. "Don has been a major contributor to the success of our defense since 2012, and especially since he became defensive coordinator four years ago. He has done a great job. Now it is time to pursue other opportunities.

"Sometimes the moment comes, and it's the right time. I am personally grateful for our friendship and for everything he has done in Baltimore."

There were members in the organization who were caught off guard by the parting of ways with Martindale. The decision came 12 days after the Ravens' season-ending, 16-13 overtime loss to the Pittsburgh Steelers and came after Martindale had participated in personnel meetings last week. Martindale also was asked to address the players in the final team meeting a day after the season ended.

The move was announced while the Ravens' brain trust -- Harbaugh, owner Steve Bisciotti and general manager Eric DeCosta -- was holding its annual organizational summit.

Baltimore ranked No. 25 on defense last season, the first time the Ravens had finished out of the top 10 in Martindale's four seasons as defensive coordinator. The Ravens also allowed the second-most yards (363.4) in the franchise's 26-year history, according to ESPN Stats & Information research.

Martindale, 58, had been with the Ravens since their 2012 Super Bowl season and was known for his ultra-aggressive style. The Ravens regularly ranked among the highest-blitzing teams.

This season, the Ravens struggled after losing three of their four starters in the secondary -- cornerbacks Marlon Humphrey and Marcus Peters and safety DeShon Elliott -- to season-ending injuries. Baltimore had trouble stopping teams late in games, forcing turnovers and preventing big plays in the passing game.

The Ravens gave up the most completions of 20 or more yards in the NFL (74) and 40 yards or more (16). Baltimore also managed just 34 sacks this season, which ranked 22nd in the league.

This was unlike any season under Martindale, whose defenses ranked No. 1 in 2018, No. 4 in 2019 and No. 7 in 2020. He had been considered a head coaching candidate, even interviewing for the New York Giants job in 2020.

Martindale was known for his colorful comments during press conferences and for being a players' coach. During preseason games, Martindale allowed some older players to call the defense in the second half.

Wink was a Real one Respect Big Dawg #TownBiz

— Marcus Peters () January 22, 2022

The Ravens have traditionally hired from within at defensive coordinator. Internal candidates include defensive line coach Anthony Weaver and defensive pass game coordinator Chris Hewitt.

It's also possible the Ravens could bring back former inside linebackers coach Mike Macdonald, who was long believed to be the heir apparent to the coordinator job. Macdonald was the defensive coordinator for the Michigan Wolverines last season.

Another option is former Ravens defensive line coach Joe Cullen, who was defensive coordinator for the Jacksonville Jaguars last season.

The firing of Martindale comes at a time when Baltimore is facing a potential defensive rebuild. Aside from the pass rush, the Ravens have a number of areas to address on defense this offseason with the team perhaps looking to add four new starters on that side of the ball.

Defensive linemen Calais Campbell and Brandon Williams -- who combined for 1,012 snaps this season -- are entering free agency this offseason, and middle linebacker is also an area of concern after the team moved former first-round pick Patrick Queen out of that spot.

The secondary, meanwhile, needs a playmaking safety and a No. 3 cornerback.

This coaching change shows that the last-place Ravens (8-9) are not staying with the status quo after becoming the first team in the past 19 seasons to go from being the No. 1 seed in the conference to failing to make the playoffs six weeks later.