Guy ran the defenses in the best two-year run in FIU history - 8-5 in 2017, and a school-record 9-4 with a win in the Bahamas Bowl last season. He says he's stepping away to tend to personal family responsibilities.
Guy has been on football sidelines for more than 30 years, with his relationship with Davis dating back to the early 1980s at Oklahoma State. Guy played for the Cowboys when Davis was an assistant at the school.
FIU has yet to announce Guy's replacement as coordinator.
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