It's not exactly a high-octane swap, but Acho gives Kelly a young, second-year linebacker to add to the mix. He never started for the Browns, landing on season-ending injured reserve in August after being selected in the sixth round of the 2012 NFL Draft out of Texas. His brother, Sam Acho, has started 26 games at linebacker for the Arizona Cardinals over the past two seasons.
Lewis is another fringe performer. With just 36 carries for 171 yards in his first two seasons, the 2011 fifth-round draft pick fell behind Bryce Brown on the depth chart last season. Reports suggested the 5-foot-8, 195-pound Lewis wasn't a fit for Kelly's system, and the Eagles have tried to shop him before, according to Rapoport.
Now they've succeeded, and we're one move closer to seeing what Kelly's Eagles will look like in 2013.
Follow Marc Sessler on Twitter @MarcSesslerNFL.