PHILADELPHIA — After a dazzling performance in a 31-20 win at Tampa Bay, all you heard around these parts was how quarterback Nick Foles was ready to replace the injured Michael Vick as the starter.No, he doesn’t have the speed or arm strength rookie coach Chip Kelly supposedly needs to run his offense. But his accuracy, quick release and decision-making would more than make up for it.After watching that same Foles misfire time and again, overthrowing or simply failing to connect with open receivers in a 17-3 loss to the Dallas Cowboys on Sunday, it appears Vick’s job will be waiting for him as soon as he’s healthy enough to reclaim it. While those receivers had their share of drops and star running back LeSean McCoy never got on track, Foles’ futility stood out against the 30th ranked defense in the league.“He was off,” said Kelly, after the former Austin Westlake star completed 11 of 29 passes for 80 yards, before a sack on the final play of the third quarter ended his day with a head injury. “At times we had guys open and didn’t put the ball on them, but there were other times we didn’t help him either.“They didn’t do anything we hadn’t prepared for. You hopefully chalk it up as just a bad day.”Foles’ injury forced rookie Matt Barkley, a fourth-round pick from USC, to make his unexpected debut, just as Foles was suddenly thrown into action when Vick went down against these same Cowboys here last year. Barkley was intercepted three times.“I thought I was ready to go in,” said Barkley, who finished 11-for-20 for 129 yards. “I was trying to do everything I could — maybe too much — trying to extend plays.”It’s anyone’s guess who’ll be behind center when the Eagles take on the New York Giants next Sunday afternoon in Philadelphia.