Alexander Mattison's season-ending neck injury redefines Miami's backfield. De’Von Achane remains the centerpiece, with Jaylen Wright and rookie Ollie Gordon II providing depth behind him. The Dolphins added Aaron Shampklin and Mike Boone to test veteran options, signaling a shift toward experienced relief behind Achane as the starter absorbs a heavier workload. Shampklin, Harvard alum with Steelers ties, brings a quirky path to the league, while Boone offers 72-game, four-team familiarity. In fantasy terms, expect Achane to carry a bigger share, Wright to operate as a solid complementary piece, and Boone/Shampklin to mix in on passing downs and short-yardage as the Dolphins navigate Week 1 and beyond.

The roster churn underscores the volatility of RB depth in the NFL. Mattison’s exit leaves a gap that the Dolphins are filling with veteran experimentation rather than immediate star power. Wright’s role could stabilize as the clear #2, but the true upside resides in Achane’s expanded touches and the team's willingness to lean on him in early-down and goal-line situations. Shampklin’s Harvard arc and Boone’s career resume add intrigue for late-roster bets and weekly DFS pivots while Miami maps a plan to stay balanced without sacrificing explosiveness.