PHILADELPHIA (AP) — When DeMarco Murray traded the blue star on his helmet for silver and white wings, the balance of power in the NFC East shifted from the Dallas Cowboys to the Philadelphia Eagles.That might be the difference in a division that's had four different champions in the past four years.Last season, Murray helped the Cowboys end a string of mediocre seasons with a record-setting performance that catapulted Dallas to 12 wins and its first division crown in five years.But the All-Pro running back got a better free-agent offer from Philadelphia, where Chip Kelly overhauled the roster following a 10-win season that wasn't good enough for a playoff spot.Murray is one of five new starters on an offense that has thrived since Kelly's arrival in 2013.