The Philadelphia Flyers' season just got a whole lot crappier ... 'cause on the day they fired their head coach amid a losing skid, a police K9 defecated all over their center-ice logo.
Just hours after the team canned Alain Vigneault, several dogs from the Philadelphia Police Dept. took a trip to Wells Fargo Center ... and you can see in video of their visit, things got messy quickly.
One of the dogs walked all the way out to the red line ... popped a squat and then let its bowels go.