Tannehill opted for the procedure, which officially rules him out for the entirety of the 2017 season.
Ryan Tannehill has opted for season-ending surgery to repair a torn ACL in his left knee, according to the Miami Hearld's Armando Salguero.
Tannehill left the Dolphins' practice on Thursday after his knee appeared to buckle in a non-contact situation. Miami then convinced Jay Cutler to postpone his broadcasting career to join the team on a one-year deal that will could pay him up to $13 million.
The decision to opt for surgery came after Tannehill discussed his options with head coach Adam Gase on Friday.
Tannehill, 29, threw for 2,995 yards, 19 touchdowns and 12 interceptions last season in leading the Dolphins to a 10-6 record and a playoff berth. It's an extremely unfortunate turn of events for Tannehill, who many in the Dolphins organization believed was poised for a big season. He will enter the 2018 season at 30 years old and has no guaranteed money left on his contract.