Philadelphia sports fans can be quite… intense, to put it lightly. This is generally considered to be a universal truth by many fans. The most infamous example of this is the Philadelphia Eagles Santa Claus incident of 1968. This incident is so infamous, it even has its own Wikipedia page! 55 years later, and Eagles head coach Nick Sirianni is still being asked about this incident, per Eliot Shorr-Parks.

For those out of the loop: the Eagles-Santa Claus incident happened back in 1968, in the midst of arguably Philly’s worst season in the NFL. During Week 14 (then the final game of the season), Philly fans pelted a man in a Santa Claus costume with snowballs. The incident has since been used as an illustration of the intensity of Philly sports culture, both in a good and bad way.

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In his response, Nick Sirianni acknowledged the intensity of Eagles fans, but said that it motivates him to be better. That type of attitude is what endeared him to Philly fans. That, and his team’s success this season. When the Eagles go 14-3 in the regular season, there’s hardly any reason for fans to boo. They certainly found some perfect instances to do so, though.

The Eagles will look to keep the boo-birds away as they face the San Francisco 49ers in the NFC Championship Game. These have been, pound-for-pound, the two best teams in the conference. It’s the battle of an unstoppable force and an immovable object. Who will come out on top of this titanic matchup?