"We are fired up to have Dirk join our staff as our offensive coordinator," Falcons head coach Dan Quinn said in a statement. "His experience and familiarity with our division will also pay dividends as we move forward."
Koetter, who turns 60 next month, previously was the Falcons' offensive coordinator from 2012 to 2014. He helped the Falcons to the NFC Championship Game in 2012 as the offense averaged 26.2 points per game and 369.1 yards per game. During his first three-year stint in Atlanta, the Falcons averaged 363.5 yards per game, 277.2 passing yards per game and 24.0 points per game.
Quarterback Matt Ryan praised Koetter in the past for enhancing his game.
"Dirk taught me a lot about being confident in what we do," Ryan said before the 2016 season opener. "I think he believed in -- and rightfully so because, at the time, we had a lot of really good players -- he believed if I was comfortable with it, go. It made me take ownership of what I liked, what I didn't like. He pushed me to be better in that department."
Quinn interviewed Koetter, Mike Mularkey and Darrell Bevell for the job after firing Steve Sarkisian, who spent the past two seasons as the offensive coordinator. Bringing back Koetter means the comfort of a familiar face for Ryan rather than having to adjust to a new playcaller.
Mularkey, who parted ways with the Tennessee Titans after going 20-21 in parts of three seasons as their head coach, was named the Falcons' tight ends coach on Tuesday. Mularkey also previously served as offensive coordinator in Atlanta.
"Mike brings over 20 years of experience in our league as a former playcaller, head coach and as a player, and we are pleased to have him join our staff," Quinn said. "He has a good feel for our offense, both in the run game and the pass game, and we feel he will be able to add to the strengths of our tight ends group as we head into 2019."
Having Koetter and Mularkey, two former NFL head coaches, should help Quinn in terms of game-day responsibilities such as clock management. Quinn said during his postseason news conference that he would find someone on staff to help with those responsibilities.
An adjustment will have to be made by Koetter, with Quinn wanting to keep the same outside/inside zone scheme in place. The relationship between Koetter and offensive line coach Chris Morgan will be important in terms of the offensive philosophies coming together in unison.
Koetter is known more for engineering a strong passing attack and is certain to utilize Ryan's strength of running the no-huddle, as in the past. Before he was fired by Tampa Bay after a 5-11 season, Koetter's Buccaneers led the league at 320.3 passing yards per game and were third in total yards at 415.5 yards per game.
The Falcons finished the '18 season sixth in total yards (389 yards per game), fourth in passing offense (290.8 passing yards per game) and 10th in scoring offense (25.9 points per game). The area in which they struggled the most was running the ball, finishing 27th out of 32 teams with 98.3 rushing yards per game.
Koetter's rushing offense the first time in Atlanta never averaged more than 93.6 yards per game. The Falcons hope the running attack improves next season with the return of two-time Pro Bowler Devonta Freeman from groin surgery and with more physicality and perhaps a couple of new faces along the offensive line.
Koetter, who started his coaching career at the high school level in 1983, has been the offensive coordinator for the Jacksonville Jaguars, Buccaneers and Falcons in the NFL along with various college stops.
Quinn made significant changes after a 7-9 finish, firing all three of his coordinators -- Sarkisian, defensive coordinator Marquand Manuel and special-teams coordinator Keith Armstrong. Quinn will take over the defensive coordinator role. A new special-teams coordinator has yet to be announced.