ATLANTA -- After 14 seasons in which he became the best quarterback in franchise history, Matt Ryan is moving on from the Atlanta Falcons.

Atlanta traded Ryan on Monday to the Indianapolis Colts in exchange for a 2022 third-round draft pick, the team announced.

The Falcons moved quickly to add Ryan's possible successor, agreeing to a two-year contract with quarterback Marcus Mariota, who is familiar with coach Arthur Smith's offensive scheme from their time together with the Tennessee Titans. Mariota's deal is worth two-year, $18.75 million, a source told ESPN's Adam Schefter.

Smith and Mariota worked together in multiple capacities in the five years they were together with the Titans, including Mariota's six games as a starter during the 2019 season. That was Smith's first year as the Titans' offensive coordinator.

The Colts were desperate for a quarterback after they traded Carson Wentz to the Washington Commanders for third-round picks in 2022 and 2023. Ryan will be the Colts' seventh different Week 1 starter in as many years and the fifth different starting quarterback in coach Frank Reich's tenure.

The Colts and Ryan are restructuring his contract, with a source telling ESPN's Jeremy Fowler that the two years and $53.9 million remaining on his deal are now guaranteed in some form, largely in full, which also could provide Indianapolis with some cap relief.

The third-round pick the Colts are sending the Falcons for Ryan is their original third-rounder, No. 82 overall, not one of the picks they got from Washington for Wentz, a source told ESPN's Dan Graziano.

"We're thrilled we had a chance to acquire a proven veteran in Matt Ryan who brings tremendous experience to our team," Colts general manager Chris Ballard said in a statement. "Matt's leadership and skillset will complement our roster's growth and success. He's long been a great ambassador for the NFL and the Atlanta Falcons, and we're excited he can continue his accomplished career in Indianapolis."

Reich added in a statement that he has "long admired Matt for his steady, methodical approach to the game."

The Colts have been looking for a long-term answer since Andrew Luck retired in August 2019. Ryan will be the second quarterback at the tail end of his career the Colts have acquired in the past three seasons. Veteran Philip Rivers retired at the end of the 2020 season after just one season in Indianapolis. Ryan is signed through the 2023 season.

The Colts' odds to win the Super Bowl improved slightly after the trade, with Caesars Sportsbook moving Indianapolis from 30-1 to 25-1.

Conversations about Ryan's departure picked up at the start of the new league year, when the Falcons became part of a group of teams inquiring about trading for quarterback Deshaun Watson. Higher-ups throughout Atlanta's organization met with Watson, who is from Gainesville, Georgia, and tried to lure him to the Falcons despite 22 open lawsuits filed by women accusing the quarterback of sexual assault and sexual misconduct.

As part of that pursuit, the Falcons and Ryan pushed back a $7.5 million roster bonus to Monday to both let the Watson courtship play out and allow Ryan to seek out trade partners. Watson ended up waiving his no-trade clause to go to the Cleveland Browns, but it also put the Falcons in a position where they had to publicly seek out a succession plan for Ryan.

The trade will leave a dead-money charge of $40.525 million on the Falcons' salary cap this season. It's the largest known dead-money charge for any player all time, according to ESPN Stats & Information research.

Atlanta now has more than $62 million in dead money for the 2022 season since it also has $15.5 million on the books for last year's Julio Jones trade and more than $4 million for releasing Dante Fowler Jr. earlier this year, along with a couple of other moves.

Weeks earlier, during Super Bowl week, Falcons owner Arthur Blank said the team had contemplated a succession plan for Ryan the past couple of seasons. Pursuing Watson clearly became one succession option. Now the Falcons will have to push that plan further.

"Matt Ryan has been the epitome of a franchise quarterback during his time here in Atlanta. He has represented this organization with great class, professionalism and leadership, both on and off the field, over the past 14 years," Blank said in a statement. "It is difficult to overstate what he has meant to me personally, our organization, his teammates and our fans.

"From his first day in the building, Matt has given his all in the pursuit of winning a championship for Atlanta. His arrival in 2008 instantly made us a contender in the NFC and he's been our quarterback through the most successful era in Falcons history. Matt led us to the playoffs six times, including two NFC Championship games, and the first Super Bowl appearance under my stewardship of the franchise. He holds every significant passing record in club history, is an All-Pro, an NFL MVP and is without question one of the greatest players in Falcons history. He will one day be added to our Ring of Honor, and it is my belief that a bust in Canton will follow in short order.

"This business is not without its difficult decisions, and while this is one of the most difficult decisions we have faced as a club, we feel it is in the best long-term interests of both the Atlanta Falcons and Matt Ryan."

Once the season was over, Smith continually praised Ryan but stopped short of committing to him to being the team's quarterback in 2022 -- continuously saying he didn't want to back himself into a corner despite how much he respects the veteran leader.

"I've got so much respect for Matt Ryan and what he's meant to this franchise and to me personally in our one year together. Matt was the ultimate professional and teammate every day. I'm thankful for our time together and wish he and his family the best as they transition to the next chapter of his professional journey," Smith said in a statement.

Ryan, meanwhile, made it clear in January that he hoped to stay with the club for his 15th season -- something he'd said each time he'd been asked about it for months. He said he believed in Smith, in what the Falcons were building and in what they did with the roster they had.

Ryan, who turns 37 in May, had been a stalwart for the Falcons since being drafted No. 3 overall in 2008 by the club. The Falcons had hoped he would be the next franchise quarterback following Michael Vick, whom the team moved on from after a dogfighting scandal that sent him to prison.

Almost immediately, Ryan proved to be a good selection. His first pass was a touchdown -- 62 yards to Michael Jenkins -- and he ended up as the NFL Offensive Rookie of the Year in 2008. The 6-foot-4, 217-pound player had been one of the team's leaders since, a durable player at the most important position in sports.

In 14 years in Atlanta, he missed only three games -- two in 2009 and one in 2019. He threw for at least 4,000 yards every season from 2011 until last season, when he threw for 3,968 yards. He has had at least 20 touchdown passes every year since his rookie season in 2008, when he had 16.

Ryan made the Pro Bowl four times with the Falcons, but no season was more impressive than in 2016, when Ryan completed 69.9% of his passes for a career-high 4,944 yards and 38 touchdowns with seven interceptions.

He was named the NFL's Most Valuable Player that season and led Atlanta to Super Bowl LI against the New England Patriots. That Super Bowl will be one of his lasting legacies with the Falcons. Atlanta held a 28-3 lead over the Patriots in the third quarter but ended up losing 34-28 in overtime.

Ryan and the team made the playoffs the next year, in 2017, but the Falcons have not had a winning record at any point since.

In those four seasons, Ryan has been sacked 40 or more times in each season. He rarely has had competent defenses around him over the past four seasons and last season played with a roster that saw the trade of Jones, WR Calvin Ridley missing three-quarters of the season so he could focus on his mental health and WR Russell Gage injured for a quarter of the season.

Four straight losing seasons combined with a massive contract -- Ryan had a cap hit of over $48 million -- made Ryan a potentially expendable player. And now, like so many of his contemporaries -- Tom Brady, Peyton Manning, Matthew Stafford and Russell Wilson -- he'll finish his career somewhere other than where it started.

Mariota, 28, spent the past two seasons with the Las Vegas Raiders and has dealt with numerous injuries, appearing in one game in 2020 and 10 games in 2021. The 2014 Heisman Trophy winner from Oregon and No. 2 pick of the 2015 NFL draft initially signed a two-year, $17.6 million free-agent contract with $7.5 million guaranteed to be a change-of-pace quarterback behind Las Vegas starter Derek Carr.

Last season, Mariota saw action in 10 games. In the season-opening win against the Baltimore Ravens, he played one snap, breaking off a 31-yard run. But he was shaken up on the play and went on IR with a quadriceps injury and did not play again until Week 7, after coach Jon Gruden resigned. Mariota was mostly used in specific packages on the season and rushed for 87 yards, on 13 carries, and a TD.

Mariota has never played a full season and last started as many as 15 games for the Titans in 2017. Since then, he has appeared in 14, seven, one and 10 games, starting 13, six, zero and zero, respectively.

He has thrown for 13,437 yards and rushed for 1,574 with 77 passing touchdowns, 45 interceptions and 13 rushing scores in seven NFL seasons.

ESPN's Mike Wells, David Purdum and Paul Gutierrez contributed to this report.