"It's safe to say he'll be the next coach of the Falcons," a source close to Quinn told ESPN.com Sunday night.
The Falcons were prohibited from agreeing to a contract with Quinn until after the Seahawks finished competing in Sunday's Super Bowl. Now that the season has concluded, the details of Quinn's contract will be worked out, the source said.
ESPN's Chris Mortensen, citing multiple sources, said Falcons owner Arthur Blank will have his private jet fueled and ready Monday to escort Quinn to Atlanta for the news conference.
Quinn would not discuss the move after the Seahawks' 28-24 loss, saying he wanted to "make everything about tonight" about Seattle's players, and as well as the Patriots'.
"In respect to this game, what a terrific game we were all a part of," Quinn said. "So for tonight I'd like to make the focus all about our players, both teams'. It was a great contest. You could see how hard guys played. As a coach, that's really what you're looking for, great effort first. ... You see the guys in the locker room, they gave everything they had. You can't ask for more than that as a coach."
Quinn, 44, spent the last two seasons as the Seahawks defensive coordinator after holding the same position as the University of Florida. He emerged as the leading candidate for the Falcons' job after the first round of interviews.
"It really wasn't a time for that," he said on whether any of the Seahawks players discussed his move. "It was more how do we come to grips with this. It was such a hard time at the end. Just my respect for so many of these players is so high and we're so connected. I really feel for them. They put everything they had into this."
Quinn got his coaching start in 1994 as the defensive line coach at William & Mary. His first NFL job was as a defensive quality control assistant with the San Francisco 49ers in 2001. But his ascent occurred over the last two seasons with the Seahawks, where he orchestrated a defense that ranked first in seven different statistical categories in 2013 and in five different statistical categories this past season. Quinn's defense was an integral part of two Super Bowl runs.
Quinn will inherit a Falcons team sorely in need of defensive facelift. Atlanta surrendered a league-high 398.3 yards per game in 2014 and had the NFL's worst third-down defense, allowing opponents to convert 46.8 percent of the time. By contrast, Quinn's '14 Seahawks ranked first in the league in yards allowed per game (267.1), passing yards allowed per game (185.6) and points allowed per game (15.9) The Seahawks had four Pro Bowlers on defense, including three in the secondary.
Blank implied Quinn would have control of the Falcons' 53-man roster when asked about Julio Jones getting a long-term contract.
"Well, I think it's a decision that the head coach will look at the talent on the roster," Blank told ESPN.com. "Julio's been a great player for us and a great talent, and he represents us on the field and off the field as well as anybody else. As the owner, it's not my decision to make. The new coach will spend a great deal of time assessing the roster and all of our players, and obviously Julio is a critical one."
Quinn will have the challenge of adjusting to his new role as a first-time head coach. The Falcons went the same direction with their previous coach when Mike Smith was hired in 2008 following a five-year stint as the Jacksonville Jaguars' defensive coordinator. Smith went on to be the winningest coach in franchise history (66-46) before being fired following a 6-10 finish this past season.
Pieces of Quinn's new staff are already in place, with Kyle Shanahan set to be his offensive coordinator and Richard Smith the defensive coordinator. Quinn's longtime friend, Raheem Morris, will be the assistant head coach in charge of defensive backs.
And Quinn will retain at least four members of the previous coaching staff: special teams coordinator Keith Armstrong, defensive line coach Bryan Cox, wide receivers coach Terry Robiskie, and former assistant offensive line coach Wade Harman, who will now coach the tight ends. Running backs coach Gerald Brown could return, too.
Quinn was in the early stages of his coaching career at Hofstra University when Morris played defensive back there and the two went on to coach on the same staff at the school.
Quinn was the defensive line coach under Richard Smith when Smith was the Miami Dolphins' defensive coordinator back in 2005, and they also coached together with the 49ers. Quinn and Armstrong worked together with the Miami Dolphins, while Quinn and Cox worked together with the New York Jets.
A native of Morristown, N.J., Quinn was defensive lineman at Salisbury State (Md.) University. He recorded 145 career tackles, eight tackles for losses, one sack and one interception in 32 collegiate games played.
Some of Quinn's coaching influences include Seahawks coach Pete Carroll, current Alabama coach and former Dolphins coach Nick Saban, and the late Joe Gardi, who was the defensive coordinator for the Jets during the days of the "Sack Exchange." Gardi was the head coach at Hofstra when Quinn was an assistant at the school.
Information from ESPN.com's Jim Trotter was used in this report.