It's not just teams that get into heated battles on the field or court.
Their mascots, cloaked in costume to entertain fans, sometimes find themselves in hot water.
Some get arrested for crowd surfing. Others start brawls with players or the other mascot. The unfortunate few receive a 15-yard unsportsmanlike penalty from referees.
No matter the sport, mascots have been known to get frisky.
Here are 15 of the worst-behaved mascots of all time.