Plenty has been made of Blas Perez' red card against the Sounders, but what would the correct interpretation of the FIFA Laws of the Game have been? Here's the play in question, with the clearest angles running from 0:53 to 1:07:

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Here's how FIFA defines a red card, with numbers added by me:

A player, substitute or substituted player is sent off if he commits any of the

following seven offences:

1 - serious foul play

2 - violent conduct

3 - spitting at an opponent or any other person

4 - denying the opposing team a goal or an obvious goalscoring opportunity by deliberately handling the ball (this does not apply to a goalkeeper within his own penalty area)

5 - denying an obvious goalscoring opportunity to an opponent moving towards the player’s goal by an offence punishable by a free kick or a penalty kick

6 - using offensive, insulting or abusive language and/or gestures

7 - receiving a second caution in the same match

Serious foul play (1) is the only option that applies in this case. Violent conduct (2) is only relevant "when not challenging for the ball." Thankfully, there wasn't any spittle (3) or middle fingers (6) involved, and that play was as far from a clear goalscoring opportunity (4 & 5) as you can get. Also, Blas wasn't even carrying a yellow (7). Here's does FIFA define "serious foul play?" Here it is, again with my numbers added:

1 - A player is guilty of serious foul play if he uses excessive force or brutality against an opponent when challenging for the ball when it is in play. 2 - A tackle that endangers the safety of an opponent must be sanctioned as serious foul play. 3 - Any player who lunges at an opponent in challenging for the ball from the front, from the side or from behind using one or both legs, with excessive force and endangering the safety of an opponent is guilty of serious foul play.

Now that we're clear on the rules, let's leave intent out of the discussion. That word doesn't show up anywhere in the description of card-able offenses.

But on the other side, there's also no mention of blood or other injury in the rules.

Blas doesn't lunge (3) at Gonzalez, in fact it's pretty much the other way around.

When considering 1 and 2, re-watch the play and pretend that Gonzalez isn't there. There is nothing in any way unnatural about the way Blas' arms move within the act of jumping and heading the ball.

We established earlier that intent and injury, the two factors most-often shouted on the two sides of red card debates, don't matter you're left with simply with Blas' actions in a vacuum.

Perez' elbow didn't hit Gonzalez' face because he was excessive, or brutal. It was Gonzalez lunging his face into a dangerous spot that caused him to bleed. Mark Geiger got this call wrong.

Then why was Blas given the red card?

Put simply, Seattle's fans are the ones who earned this call. Every study of home field advantage I've ever seen, notable a couple chapter in Scorecasting, shows that the biggest driver of home field advantage in any sport is driven by referee decisions. In soccer they call fouls in dangerous spots and, yes, give cards far more often to the visiting team.

Mark Geiger was intimidated by the CenturyLink crowd, and he handed out an unjustified card. Now it's up to the Inferno, Dallas Beer Guardians, and everyone else in Frisco to influence the refs on FC Dallas' home turf.