Ryan Tannehill's injury looms large over Dolphins' playoff hopes

MIAMI GARDENS, Fla. -- The Miami Dolphins were able to celebrate a big December win Sunday over the Arizona Cardinals to improve to 8-5 on the season.

But those good vibes were short-lived.

The bigger story coming out of Miami’s 26-23 victory was the left knee injury sustained by quarterback Ryan Tannehill. The Dolphins’ $96 million quarterback was hit low late in the third quarter by Cardinals defensive tackle Calais Campbell and knocked out of the game. Backup Matt Moore played the rest of the game for the Dolphins -- and may have to play next week and/or the rest of the season depending on the severity of Tannehill's injury. Tannehill left the field Sunday on a golf cart and was on crutches in the locker room, which are not good signs.

According to head coach Adam Gase, the Dolphins fear it is a left ACL tear.

"We don't have [it] officially yet," Gase said, "but it doesn't look good."

Here is the harsh reality facing the Dolphins: They are not a playoff team this season without Tannehill under center. Tannehill isn’t the Dolphins’ best player, but he is one of their most important. Tannehill must return sooner rather than later for Miami to have a chance at the postseason.

Despite a loss by the Denver Broncos (8-5) Sunday, the Dolphins remain on the outside looking in via tiebreakers for the final AFC wild-card playoff spot and have little margin for error. The Dolphins will play three straight divisional games at the New York Jets, at the Buffalo Bills and at home against the New England Patriots to wrap up the regular season.

This is not a knock on Moore, who is a capable backup, but the Dolphins need more than that at this crucial point of the season. Moore has thrown just 16 passes in the past four seasons. It’s asking a lot of him to get Miami over the hump and secure its first playoff berth in eight years.

The Dolphins and Cardinals (5-7-1) got off to an extremely sloppy start Sunday. The teams combined for seven turnovers, including five in the first quarter. Miami had momentum and a 21-9 lead until Tannehill's injury. After the Cardinals tied it at 23-23 with 3:01 to play, the Dolphins needed field goal by Andrew Franks at the buzzer to seal it.

How important is Tannehill to Miami? Look no further than the past two weeks.

Tannehill threw three interceptions in last week’s blowout loss to the Baltimore Ravens and bounced back with three touchdowns against Arizona to put Miami in position to win Sunday. The Dolphins clearly will only go as far as Tannehill takes them.

But if Tannehill is done for multiple games or perhaps the rest of the season, this is where the postseason push ends. It's been an interesting ride with plenty of ups (such as a six-game winning streak) and downs (such as a 1-4 start). But this is an injury the Dolphins can ill-afford.