Miami Dolphins quarterbacks Ryan Tannehill, right, and Matt Moore chat...

Miami Dolphins quarterbacks Ryan Tannehill, right, and Matt Moore chat before an NFL game New England Patriots in Miami Gardens, Fla., Jan. 3, 2016. Credit: AP / Wilfredo Lee

DAVIE, Fla. — Miami Dolphins quarterback Ryan Tannehill has been ruled out of Sunday’s playoff game at Pittsburgh, and backup Matt Moore will start for the fourth week in a row.

The Dolphins determined Tannehill isn’t ready to return from a sprained left knee he suffered in Week 14. The decision to rule him out came before Thursday’s practice.

Moore, a 10th-year pro, is 2-1 as Tannehill’s replacement and will make his first career postseason start. Moore has eight touchdown passes, three interceptions and a quarterback rating of 105.6, which is higher than Tannehill’s career-best 93.5 this year.

Tannehill hadn’t missed a game in five NFL seasons until he was sidelined against the Arizona Cardinals. He’s never played in the postseason, and the playoff game will be Miami’s first since 2008.

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