Andy Reid's next change?

Interim Eagles defensive  coordinator Todd Bowles has been heavily involved in game plans and almost certainly was calling the coverages during games an NFL source said.

The fourth quarter change in the Eagles' coverage of Lions receiver Calvin Johnson had someone else's fingerprints on it per the source.

The Eagles were doubling Johnson with cornerback Nnamdi Asomugha and a safety until varying the coverage with other defenders. While Asomugha was puzzled by the shift in tactics, head coach Andy Reid denied the coverage changed significantly.

Reid on Tuesday canned Castillo, who had been with him since 1999. Castillo was offensive line coach until the 2011 season. He was defensive coordinator for 22 games. The Eagles are 11-11 in those games including 3-3 this season.

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