The Dolphins announced the move, which had been expected, hours before the NFL draft began Thursday.
Tannehill was the eighth overall pick of the 2012 draft. He has started every game in his first three NFL seasons and improved each year. Last season he threw for 4,045 yards with 27 touchdowns and 12 interceptions, and his passer rating was 92.8.
The 2016 salary will be a big increase for Tannehill after making a total of $12.7 million in the first four years of his contract.
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