The Eagles took a two-score lead into the fourth quarter Sunday but gave up 18 unanswered points to lose 21-17 to the Denver Broncos at Lincoln Financial Field. Here are five things we learned about the Birds, who suffered their first home loss since September of last year against Atlanta.

The Eagles blew a two-score lead and lost to the Denver Broncos, 21-17, on Sunday to suffer their first loss of the season.

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"I've been around this long enough where calls, they balance each other out," Eagles coach Nick Sirianni said after a loss to the Broncos.

There was one more controversial non-call, on the Broncos' drive after the Eagles had to punt because of Barkley's penalty. On 2nd-and-6 from the Broncos' 47, Nix was under a heavy rush and tried to throw the ball away before taking a sack.

On third-and-2 from Philadelphia’s 29-yard line, Eagles rookie safety Drew Mukuba wrapped up Broncos running back RJ Harvey in the flat. As Harvey fell to the ground, Baun dove on top of him to finish the tackle, drawing a 15-yard flag for a late hit.