Major League Soccer's biggest rivalry hasn't even played a match yet.

Still, when Portland and Seattle meet TONIGHT in front of 36,000+ banshee-impersonating fanatics and an international TV audience (8 p.m., ESPN2), Timbers-Sounders will instantly become the league's most important rivalry.

That's right: First kick, then boom—biggest, most important rivalry in the American game.

("Bah!" say east-coasters or Los Angelinos, "We've been back-and-forth at this thing since you guys were kicking it around the minors." Whatever, dudes.)

If MLS is to thrive—perhaps survive—it's not so much that it needs Portland and Seattle, it's that it needs every city it plays in to be just like Portland and Seattle.

The Cascadia teams are the new breed in American soccer, and there's little doubt MLS wants its traits to dominate the species: Packed stadiums, whatever the size. Traveling, maniacal, chanting-their-faces-off fans. Ownership groups who attempt to prioritize those who pay for tickets. Oh, and some pretty quality soccer, which has broken out in spurts for both sides this season and leaves the clubs tied for fourth place in the West.

So, sure—rivalry-rivalry, rah-rah-rah, proceed with aggressive northward fist-shaking. But between it all, do remember the fact that tonight, "soccer fandom" will officially join a long list of things the Pacific Northwest does better than anyone else in this fine country.

More thoughts on regional superiority after the jump, including scandalous statements (not really) about Seattle from Jeremy Hall and Kenny Cooper and EXTRA TIME! links to properly propagandize you before first kick.

Should this whole soccer thing not work out, Timbers defender Jeremy Hall and forward Kenny Cooper may have a future in diplomacy.

In their final chat with the media before boarding a bus north, I tried my dangdest to bait both into saying something—anything, fellas!—demeaning or otherwise tawdry about Seattle during the lead-up to today's match. But, alas, both Timbers rose above my attempts at scandal-mongering and gave classy, diplomatic answers. Timbers 2, Yellow Journalism 0: A clean sheet for the ages.

In between my attempts at sensationalism, Hall subtly hinted at a physical match and talked about rivalries he's into, what it means to be play in the Cascadia Cup's first MLS match and how his move back to defense has worked out so far. Closest thing to bulletin-board material: "We don't want to say anything that'll add fuel to the fire for them, at least. We're just going to let it all play out on the field and hit each other for 90 minutes and see who's standing at the end."

Cooper (who I wanted to call "Congressman" after he deftly dodged my repeated attempts at muckraking) talked about what it will be like to play in the MLS' biggest rivalry game, his love for Manchester United and his respect for the Sounders. Closest thing to bulletin-board material: "I'm not sure there's a better scene set for that first road win than getting it against our rivals. So, hopefully, we can do that."

Hours away now. I'm off to catch a train, but do check back later for some live-blogging from Qwest Field. Until then ...

EXTRA TIME! Southernmost links for all of Cascadia.
• Timbers and Sounders fans' dislike for each other "is matched by the spectacle," says Brian Straus of The Sporting News.
• Seattle and Portland's mutual distaste comes naturally, according to Don Ruiz of The Olympian.
• Fans are "leading the charge" into this derby, according to Joshua Mayers of The Seattle Times, who also notes a scarf-related wager between the mayors of Portland and Seattle.
• Fans share their favorite Cascadia Cup memories, the most entertaining and mythical of which involves a flopping soccer player and a rather on-target water bottle. Slide Rule Pass has more on "The Nutstrike." Lesson: Never throw anything on the pitch (unless you can guarantee its accuracy?).
• Not convinced of the rivalry's greatness? Allow Steve Kelley of The Seattle Times and Seth Kolloen of The Sunbreak convince you in soothing, columnist tones.
• Seattle or not, the Timbers need to prove they can succeed away from the House of Pane, according to Doug Binder of MLSsoccer.com.
• The first 15 minutes of tonight's emotional match will be key for the Timbers, says Paul Danzer of The Columbian.
• The rivalry really heated up in 1977, when Sounders player/coach Jimmy Gabriel inspired his team to a victory, remembers Stanley Holmes of Sports Press Northwest.
• "There's no denying the vitriol that exists" between Portland and Seattle, according to Jeremiah Oshan of SB Nation.
• For all the off-the-field hype, tonight's match is also an intriguing clash of styles, according to Aaron Campeau of SB nation.
• The Timbers enter tonight's match "with some advantages that visitors to Qwest Field rarely enjoy," according to Sounder at Heart blogger Sidereal.
• "A lack of energy shouldn't be an issue" for either team or their fans, according to Andrew Winner of MLSsoccer.com, which also offers a nice rundown previewing the match.
• Who's holding on to the Cascadia Cup right now? If you guessed, Portland's Fernando Machiado, you'd be correct. The Associated Press' Annie M. Peterson and KGW catch up with the trophy holder.
• Seattle Times blogger Joshua Mayers predicts a 2-1 Sounders win. He would.