The Tennessee Titans placed quarterback Ryan Tannehill on injured reserve, very likely ending his season. 

Tannehill underwent tightrope surgery on his ankle last week. He was hoping to play Week 18 in a crucial game against the Jacksonville Jaguars for the AFC South title, but he'll be on the sidelines instead. 

The 34-year-old was injured during the Titans’ Week 15 loss to the Los Angeles Chargers, which couldn’t have come at a worse time. Tennessee looked destined to take the AFC South crown again until it dropped three straight.

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Ryan Tannehill passing

Ryan Tannehill of the Tennessee Titans looks to throw a pass against the Green Bay Packers during the first quarter of a game at Lambeau Field in Green Bay, Wisconsin, on Nov. 17, 2022. (Stacy Revere/Getty Images)

"Whatever the top rating on the pain scale, it was that," Tannehill said when he spoke about the level of discomfort he felt during the game against Los Angeles. Tannehill was carted off the field before returning. 

Tannehill left the game early against the Chargers and the Titans eventually lost, 17-14, pushing the losing streak to four. 

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At the same time, the Jaguars were putting together a win streak, and the division race got much closer. 

Ryan Tannehill exits the field after an injury

Ryan Tannehill of the Tennessee Titans exits the field due to an injury during the first half of a game against the Los Angeles Chargers at SoFi Stadium in Inglewood, Calif., on Dec. 18, 2022. (Harry How/Getty Images)

Now, it will be up to either rookie Malik Willis, who has struggled to transition into the NFL and lead Tennessee’s offense, or newcomer Josh Dobbs, who is set to the start against the Dallas Cowboys on Thursday night. 

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Dobbs was acquired just eight days ago by the Titans, and head coach Mike Vrabel is going to see what he’s got because either Dobbs or Willis will start the Week 18 contest in Jacksonville to determine who goes to the playoffs. 

Tannehill has had a career resurgence during his time in Nashville. He was named the NFL Comeback Player of the Year in 2019, the same year he led the league in passer rating and earned a spot in the Pro Bowl for the first time.

Ryan Tannehill vs the Colts

Tennessee Titans quarterback Ryan Tannehill throws during the first half of a game against the Indianapolis Colts at Nissan Stadium in Nashville on Oct. 23, 2022. (AP Photo/Mark Zaleski, File)

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But Tannehill has not played at quite the same level this season, averaging 211.3 passing yards per game and throwing 13 touchdowns. Those numbers could partly be due to the departure of Tannehill's top target, A.J. Brown, who was traded to the Philadelphia Eagles.