Tannehill entered the league in 2012 as the eighth overall pick with the Dolphins, but he never lived up to his lofty draft status.
Marcus Mariota has an experienced new backup.
Ryan Tannehill's days in Miami were numbered when the season ended and today they ended for good.
Tannehill's new contract is for $7 million for one season and is fully guaranteed.
Miami will receive a 2020 fourth-round pick along with a 2019 seventh-round pick in exchange for Tannehill and a 2019 sixth-round pick, a source told ESPN. Tennessee gets a 6th round pick in 2019 and Tannehill.More news: Jussie Smollett pleads not guilty to lying about attack
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Tannehill will not count against the Dolphins salary cap in 2020.
The Dolphins chose to move on from Tannehill earlier this offseason and they've spent the last few weeks actively pursuing a trade.
He was the first quarterback taken in the top round since Dan Marino.
Tannehill returned last season and helped the Dolphins get off to a 3-0 start, but he sustained a shoulder injury late in the Week 5 loss against the Cincinnati Bengals and would be forced to sit out the following five games.
The Dolphins spoke with quarterback Tedddy Bridewater, but were unable to come to a deal.
His time with the Dolphins was marred by mediocrity and injuries.
For the Titans, this is a high-end move but a smart one.