Tannehill is dealing with ACL and MCL sprains in his left knee and missed the final three games of the regular season.
With Tannehill on the shelf, veteran Matt Moore is in line to start against the Steelers. He went 2-1 for Miami to close out the season, throwing for 674 yards, eight touchdowns and three interceptions.
While Moore has never started a playoff game, the 32-year-old has 28 games of starting experience during the regular season in his 10-year career.
Prior to his injury, Tannehill was having an up-and-down season with 2,995 passing yards, 19 touchdowns and 12 interceptions. In terms of quarterback rating, his 93.5 mark paled in comparison to Moore's 105.6 in five appearances.
Tannehill did enjoy success against Pittsburgh earlier in the season, though, completing 75 percent of his passes and throwing for 252 yards in a 30-15 Dolphins victory.
Much of Miami's game plan revolved around running back Jay Ajayi in that game, and that figures to be the case once again Sunday.
The Dolphins are considerable underdogs on the road against a Pittsburgh team that is riding a seven-game winning streak, but if Moore can help pull off the upset, Tannehill will have another week of recovery at his disposal before a date with the New England Patriots.
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