In Miami, Christensen's quarterback will be Ryan Tannehill, who is 29-35 in four years as a starter and regressed in 2015, when the Dolphins finished 6-10.
Gase, who was offensive coordinator for the Bears last season, plans to call plays for Miami.
The Dolphins ranked 28th in offensive points and 26th in yards this season. Christensen is their sixth offensive coordinator since 2010, and Bill Lazor and Zac Taylor had the job this season.
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