General manager Jeff Ireland has invested early-round draft picks in Daniel Thomas and Lamar Miller the past two years. With left tackle Jake Long, cornerback Sean Smith, and wide receiver Brian Hartline also due to hit free agency, it doesn't make sense to invest heavily in an aging running back.
While the Dolphins are expected to make Bush a cursory "team-friendly" offer, the smart money is on the versatile back signing a short-term deal with a contender. Turning 28 in March, Bush is a long shot for a final mega contract even after averaging more than 1,000 rushing yards in two seasons with the Dolphins.
Keep an eye out for the Cincinnati Bengals and Detroit Lions, two teams known to be seeking a more dynamic back with pass-catching ability and the outside speed to complement short-yardage pounders BenJarvus Green-Ellis and Mikel Leshoure.
Follow Chris Wesseling on Twitter @ChrisWesseling.