Peyton Manning got to experience the "classic Philly welcome" as Santa Claus ... 'cause after he put on the red suit, he was hilariously pelted with snowballs from Ricky Watters -- and Matt Millen!
The Hall of Fame QB became the sitting duck for the holiday episode of "Peyton's Places" show on ESPN, where he's riding a firetruck inside the Lincoln Financial Field ahead of the Eagles' Christmas game.
Watters -- who played running back for Philly for two seasons -- and Millen, a former linebacker and executive in the NFL, are in the stands booing Manning .