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Tonight's match against Portugal is already being trumpeted as the biggest game in U.S. soccer history. Here's what you need to know.

If the U.S. Wins:

It's as simple as this: If the United States wins today, they advance to the knockout round with the final 16 teams. This would be the first time the Americans have ever advanced to this point in consecutive World Cups.

Since the American squad already beat Ghana in a thriller last week, if it beats Portugal today, it will ensure itself, at worst, a second-place finish in Group G (known as the Group of Death) with two victories. The top two teams advance.

If the U.S. Ties Portugal or Loses:

Be prepared to talk knowingly about the consequences should things go sour (or simply middle) for the U.S. side today. Since Germany and Ghana tied 2-2 yesterday in probably the best match of the tournament, the picture has gotten a little muddied. 

Here's how the Americans can still advance even without winning today:

- The Americans draw with Portugal and then beat or tie Germany later this week
- The Americans lose to Portugal, but still beat Germany
- Most ridiculously, the squad loses to Portugal by fewer than three goals and both contests between the U.S.-Germany and Portugal-Ghana end in draws.

The Growing Bandwagon

We are in the midst of a football renaissance here. At least, by bandwagon metrics. Official U.S. team apparel is flying off the shelves and has already outsold the 2010 World Cup total. U.S. captain Clint Dempsey's jersey is the second-best selling jersey in the world.

Speaking of Clint Dempsey

Dempsey broke his nose in the last match against Ghana and there was speculation that he might wear a mask in the match against Portugal. 

The Ghost of Landon Donovan

U.S. Coach Jurgen Klinsmann made ripples when he decided to leave Donovan, the U.S. men’s national team career scoring leader, off the roster this year. With forward Jozy Altidore nursing a hamstring injury, a major subplot revolves around how Klinsmann responds.

There are a few replacement options: young Aron Johannsson (23) or older Chris Wondolowski (31). Johannsson took over after Altidore went out against Ghana, but he didn't make a real impression. Wondolowski, while impressive, has never placed in a World Cup match.

Portugal's Injuries and Cristiano Ronaldo

Portugal is also short-handed today. Bruno Alves, the team's most experienced defender, is questionable. At the Los Angeles Times, Kevin Baxter breaks down the rest of the team's injuries and scratches:

Meanwhile Portugal, ranked No. 4 in the world, is missing four players: striker Hugo Almeida, goalkeeper Rui Patricio and defender Fabio Coentrao, all of whom are injured, and defender Pepe, who was suspended one game after drawing a red card in the opening 4-0 loss to Germany.

As everyone knows (or should know...wink), Portugal will always be a dangerous squad so long as current World Player of the Year Cristiano Ronaldo plays. He's been battling some injuries, but be sure to watch out for him. Also, maybe mention that his arch-rival Lionel Messi scored a wild game-winning goal for Argentina against Iran yesterday. The two men remain at the center of most debates in the soccer world about who is the best player in the universe right now.

The Weather

Today's match will be played in Manaus, which is actually located in a Brazilian jungle. It will be hot and muggy. No European team has ever won a World Cup played in the Americas and the climate and distance, historically, can be chalked up as a disadvantage for a team that plays in more reasonable moderate climates.  

This article is from the archive of our partner The Wire.

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