Fans running on the field is a tradition as old as sports. Whether it's going out there to celebrate, or to congratulate someone, or to get a selfie, or to just get attention, it happens. It doesn't matter the sport or venue, there has probably been a pitch invader there before.
The problem is that running on the field is usually against the law and, for very real safety concerns, stadium officials take it very seriously. When a fan gets out there, security wants to get him down and then off the field as soon as possible.
One fan at Friday's Canada vs. Mexico World Cup qualifier found out the hard way that these security guards are sometimes very athletic, quick, fast, explosive and strong. They may even have formal football training and be able to hit you with a tackle that would make Mike Ditka proud.
Let's go through this man's thoughts:
● "Hey, it'd be fun to run on the pitch."
● "It doesn't look like anyone will stop me from getting out there."
● "This is awesome."
● "La dee da daaaaaaa."