Getting to know the U.S. Open Cup, a unique event in the U.S. sporting landscape

It is often said that the Lamar Hunt U.S. Open Cup is the American equivalent of England's FA Cup. That's true, in as much as anything can be. The main similarity is that both tournaments are open to virtually everyone and bill themselves as the place were tiny, often amateur clubs get to step on the same field as the big boys in an attempt to pull off a massive upset. There is, quite literally, nothing else like this in the American sports landscape.

The histories of these giants vs. minnows tournaments are, indeed, rich with upsets and those histories date back more than 100 years. The FA Cup started in the 1870s, while the U.S. Open Cup was first played in 1914.

Rife with upsets or not, the cream tends to do what creams does. Manchester United and Arsenal have each won 11 FA Cups. In the Open Cup, the Seattle Sounders have quickly moved to the head of the class. The Sounders will be attempting to win their fourth Open Cup title in six seasons and have now advanced to five finals in that time. The Chicago Fire are the tournament's other dominant club of the MLS era, but their fourth and most recent title came in 2006.

Standing in the Sounders' way are the Philadelphia Union, a five-year-old franchise that will be playing in its first ever final.

The game will kick off on Tuesday at 7:30 p.m. Now seems like a good a time as any to get up to speed.

When you say "open to virtually everyone", is that supposed to be literal?

Well, about as literal as can be. Amateur leagues all over the country have pathways into the tournament's main draw and every professional outdoor team in the country has a way in as well. Granted, those teams don't do very well for the most part, but as recently as 2012 an amateur team from an adult league beat an MLS team.

But two MLS teams in the final, again, what happened to all the Davids?

Crushed by various Goliaths, mostly. PSA Elite were the last remaining amateur squad in this year's tournament and they got crushed 5-0 by the Sounders in the third round. Two second-division teams made it as far as the quarterfinals. The last time a non-MLS team made it to the finals was in 2008 when the Charleston Battery got there and the Rochester Rhinos were the last non-MLS team to win it in 1999.

Tell me about the Union.

The host Union got off to a rough start under head coach John Hackworth, going 3-7-5 before he was fired on June 10. Since Jim Curtin was named the interim boss, though, the Union have actually been pretty good. Under the Pennsylvania native, they've gone 6-2-4 in league play and beat fellow MLS sides New England Revolution and FC Dallas on their way to the Open Cup final.

Traditionally a pretty boring team, Curtin has opened things up a bit which has led to the Union averaging 1.92 goals per game under his tutelage as opposed to 1.47 before. Leading the line are MLS veterans Sebastien LeToux (12 goals, 6 assists) and Conor Casey (8 goals). Former No. 1-SuperDraft pick Andrew Wenger (no relation to Arsene) has also been enjoying his first extended run of success, scoring four of his five goals under Curtin. The creativity mostly comes from Argentine Cristian Maidana (nine assists) and Vincent Nogueria (three assists). Maurice Edu was the team's big offseason acquisition and he's mostly lived up to the billing, while moving around from defensive midfielder to center back.

They've also got a bit of an odd situation in goal. Zac MacMath has been their starter, but he's hovered between acceptable and cringe-worthy most of the season. The Union then signed World Cup veteran Rais Mbolhi, who's started just one game but also missed a couple while on international duty with Algeria. Who starts on Tuesday is still unknown.

They'll be playing for the club's first-ever trophy, after joining MLS as an expansion team ahead of the 2010 season.

How about the Sounders?

No MLS team of recent vintage has enjoyed more Open Cup success than the Sounders. This will be their fifth Open Cup final in six years and they've won the thing three times, including during their inaugural MLS campaign. Even going back to their days in the lower levels, they made the Open Cup semifinals in both 2007 and 2008.

But due to one of the many quirks of this tournament, the Sounders have rarely had to play road games, including none in the run-up to this final.

Still, they have to be considered the favorites. In addition to their cup-final experience, they have been the best team in MLS for most of the season. The Sounders burst out of the gates with an 11-3-2 record, hit a bit of a post-World Cup lull and have now gone 4-0-1 in their last five to comfortably sit atop the Supporters' Shield standings.

No MLS team has bigger stars or a deeper roster. United States international Clint Dempsey (11 goals, 7 assists) and former Nigerian international Obafemi Martins (13 goals, 9 assists) lead an attack that tends to score in bunches. The midfield is stacked with lesser names, but high quality guys like Osvaldo Alonso, Gonzalo Pineda, Brad Evans and Marco Pappa. But has really separated the Sounders in Open Cup competition is their depth, where veterans like Kenny Cooper, Chad Barrett and Lamar Neagle have had some of the team's bigger moments.

Leading the Sounders is Sigi Schmid, who will be coaching in his seventh Open Cup final and attempting to win it for the fifth time.

Fair to assume first-choice sides for both teams?

Both coaches said they were effectively healthy. The Union sat a few of their starters in their game on Saturday, while the Sounders used most of their normal starters. Dempsey has been complaining about fatigue lately, though, so he might be a candidate to come off the bench. Otherwise, should be pretty much the best XI vs. the best XI.

You referenced a host. Is this game not played a neutral facility?

Nope. The United States is a vast country, as you may know, and this tournament isn't exactly a huge draw. So the final has been played at one team's home stadium for most of its recent history.

Philadelphians must be killing each other for ticket, then, right?

Well, not exactly. At last count there were about 13,000 tickets distributed. A good walk-up crowd might bring it to 15,000 but it's probably not going to sell out.

How was the host determined?

Believe it or not, it used to be determined by blind bidding in which teams would effectively offer to buy the rights. But now it's a simple coin flip. They even did it in public this year.

Wait, are they even called Philadelphians?

Apparently, but their supporters group is called Sons of Ben, which is named after Benjamin Franklin. Much cooler.

Will Sounders supporters' be there in numbers?

There should be close to 300 Sounders fans in attendance. They'll be the ones wearing those outrageous neon green shirts.

How can I watch this game?

In its infinite wisdom, U.S. Soccer -- which controls the broadcast rights -- signed a multi-year deal with GolTV back in 2012. That same year, GolTV was kicked off of most cable and satellite providers in favor of BeIN Sports. Almost no cable providers carry any version of GolTV and even though DirecTV carries it, the channel is only available as part of the Spanish-language package. Up until recently, the channel wasn't even available for online streaming.

The good news is that a streaming service called KlowdTV recently signed a deal to carry GolTV, meaning it's now available to anyone with a high-speed internet connection and willing to pay the roughly $9 a month subscription fee.

Anything else I need to know?

For all its worts, the U.S. Open Cup is still pretty cool. It's the only tournament in North America where real amateurs play real professionals in matches that really matter. Of course, they are all pros by the time the finals roll around, but the teams that get here invariably take it pretty seriously. It will have all the tension we've come to expect from Cup finals and these teams are both playing well. Should be fun.