Richie Grant forces picture-perfect fumble for Falcons (0:19)

The Falcons were able to recover a fumbled ball as Grant punched the ball out of Chris' hand. (0:20).

7:49 PM AST

Dean Pees has decided to retire for the third time.

Pees told Falcons players Monday morning after the completion of his 50th year as a coach on the high school, college or professional level, a career that has spanned 12 different places, eight states and countless lives of players and young assistants.

Pees said at the start of the season that it would take a long time. There's a lot of football.

Pees has been in Atlanta for the past two seasons helping first-time head coach Arthur Smith establish a culture for his program and his defense.

During Pees' final season in Tennessee, Smith was the offensive coordinator and Pees was the tight ends coach.

It meant a great deal. Smith said there was a lot ofwisdom. It meant a lot to me that people try to learn from each other. He's been here and I'm happy about it.

More than half of the Falcons' opening-day starters were on rookies, and Atlanta found ways to improve as the season went on. The Falcons finished with aPoints Allowed of 23 and a Yards Allowed of 27.

Pees said that points allowed was the metric he used to judge his defense. He didn't coach the game after Pees was involved in an on-field accidental collision in New Orleans that sent him to the hospital. Pees returned to coaching after he was hospitalized for the second time in a year.

As Pees leaves, he feels like he is also leaving with Atlanta having a strong defensive culture and Pees said in January that he was happy with where the defense is at.

"If we were playing the same now as we were at the beginning of the year or last year, then I would say it hasn't gone like expected." Do you think we're playing better or not?

We're playing better than we were in the first half of the year, that's what I think. It is moving in the correct direction. Isn't that what you would like?

Pees have been coaching for over 50 years. He began his coaching career at a high school in Ohio and then moved to the University of Findlay in 1979 where he became the defensive coach. They won the national title.

He moved to Division I in 1983 to coordinate the defense at Miami where he implemented both 3-4 and 4-3 base defenses. He went from there to the Navy and then to the Toledo school. He went to Notre Dame and then to Michigan State with Nick.

When he needed to create advantages at Toledo, he used some defensive principles he had learned there.

Pees' philosophy of bringing pressure not just from the front but from the secondary changed during his time as a collegiate coach. You should teach concepts over positions. Players who can be used in many different ways. He made sure his safeties were aware of both safety spots.

It messed a lot of people up because they thought the team was playing a 3-4. The guy who was playing standup middle was a three-technique.

"So I started adding guys from the secondary and saying, if this is messing up the front, maybe we can screw up the quarterback by bringing secondary guys and dropping LBs into coverage and making them interchangeable and that's where it all started."

In 1998 he took the head-coaching job at Kent State, where he lasted six seasons with a 17-51 record, and went on to work as a coach in the NFL. He won a Super Bowl in 2004.

He won Super Bowl No. 2 with the Baltimore Ravens in 2012 after he became a defensive coach.

Ravens coach John Harbaugh said that Pees is one of the best defensive coordinators in the league. There's no question about it.

Less than a month after retiring for the first time in his career, Pees was hired as the defensive line coach in Tennessee by one of his players.

He retired from the defense for the second time. When Smith became the Falcons' coach, he decided to come out of retirement and host a radio show.

As Atlanta dug out of a salary- cap mess, Pees was a mentor and culture-setter for what Smith was trying to build.

The work he's put in is appreciated. Smith said that they get paid to do this but there are a lot of sacrifice. A lot of lives and the game have been impacted by Dean.