In a significant shakeup, ESPN has announced that Mike Greenberg will replace Sam Ponder as the host of “Sunday NFL Countdown.” The move comes just days after Ponder’s departure, reportedly part of ESPN’s cost-cutting efforts. Greenberg, a veteran at the network, is taking on this new role in addition to his other responsibilities, including hosting “Get Up.” With his extensive experience and deep sports knowledge, Greenberg is expected to bring a fresh perspective to the NFL pregame show.