Tannehill won the No. 1 job for Miami's opener in his rookie season of 2012 and made 77 consecutive starts before his injury last season.
Tannehill and the Dolphins elected rehabilitation and stem-cell treatment instead of surgery, and it seemed to be a good decision.
Coach Adam Gase believes Tannehill can and will help new quarterback Jay Cutler adjust to his projected role as starter. It was reinjured August 3, on a noncontact play, when Tannehill crumbled to the ground while scrambling in practice.
The 29-year-old initially injured his knee against the Arizona Cardinals in December, partially tearing the ACL. Cutler is fortunate that Tannehill and backup Matt Moore are regarded as unselfish teammates. While the Dolphins won't challenge the Patriots for the AFC East crown, they're improved roster gives them a chance to make their second straight playoff appearance if Cutler returns to form.
Tannehill had the best year of his career in 2016 with the aid of Gase, who calls Miami's offensive plays.
Tannehill's $17.98 million salary for this year is fully guaranteed.
Tannehill has thrown 24-plus touchdowns in three of his five seasons and threw 19 in 13 games last season.